Glossary – I


Iberian emerald lizard (Lacerta schrieiberi): a lizard endemic to the Iberian Peninsula (Portugal and western Spain).

Iberian Peninsula (aka Iberia): a peninsula in the southwest corner of Europe, including Spain, Portugal, and a bit of France.

IBM: an American calculator and computer company founded in 1911 that lost its technological edge in its supposed core competencies in the 1970s and became a consulting corporation, which hurt profitability not a bit thanks to sharp management.

iboga (Tabernanthe iboga): a perennial rainforest shrub native to western central Africa. The root bark of iboga contains the dissociative ibogaine.

ibogaine (C20H26N2O): a psychoactive alkaloid found in the root bark of the iboga.

IC: integrated circuit.

ice: frozen water.

icefish (aka notothenioid): a fish which lives mainly in the Southern Ocean. While most animals have 45% hemoglobin in their blood, crocodile icefish (aka white-blooded fish) have only 1%. Icefish flourish because of the high oxygen content of the cold Southern Ocean waters, and partly because oxygen is absorbed and distributed directly by their blood plasma. Oxygen solubility greatly increases when cold. The cost is that crocodile icefish expend twice as much energy in cardiac output as other icefish with higher hemoglobin concentration.

icehouse (aka ice age): a span of millions of years where the world has continental ice sheets, tending toward cool and arid climate. Contrast hothouse.

ichthyology: the study of fishes.

Ichthyosauria: an order of large marine reptiles that appeared 250 mya.

id: Sigmund Freud’s term for the desirous instinctual part of the psyche. Compare ego, superego. See demind.

idea: the representation of a concept.

idealism (aka subjective idealism, empirical idealism): the monistic epistemology that all of life’s experiences, and what can be known of reality, are entirely within the mind. Compare neutral monism. See energyism.

identity: sense of self.

ideogram (aka ideograph): a written symbol representing a concept. Compare pictogram.

ideology (politics): a doctrinal sociopolitical belief system about an ideal social order and how to attain it.

Idotea: a genus of isopod crustaceans which mostly inhabit cold temperate waters.

iguana: an herbivorous tropical lizard.

igneous (rock): rock formed by cooling and solidification of magma or lava. Compare sedimentary and metamorphic. See basement.

ignorance: a state of unknowing. There are 2 types of ignorance: fact-ignorance (fignorance) and perspective-ignorance (pignorance). Fignorance is not knowing the salient facts of a subject. Pignorance arises from incognizance of reality.

iguana: a genus of herbivorous tropical lizards.

ileocecal valve: a one-way passage from the small intestine and the appendix to the large intestine. The valve’s critical function is to limit reflux of colonic contents back into the ileum, the final section of the small intestine.

illusion: mistaken perception; something deceptive by a false impression.

illusion of control: the belief that one has more control over events than merited; named and documented by Ellen Langer in 1975.

illusion of knowledge: someone thinking that they know more than they do.

illusion of transparency: the belief that one’s mental state is more apparent to others than it is.

imagine: to form concepts which are not adherent to sensation.

imaginability heuristic: the mental shortcut of assigning likelihood based on the ease with which a scenario can be imagined. Compare availability heuristic.

imaginary number: the square root of a negative number.

imagination: the faculty for forming counterfactual mental images and perceptions. Compare dream.

imagination inflation: a false memory of having done something which was only imagined. See observation inflation.

imagine: to form concepts in the mind which are not strictly adherent to sensation.

immanence (religion): the belief that there is an active divine presence in the material world. Contrast transcendence. Compare supremism.

immanent: operating or being within the conceptual realm considered; indwelling; intrinsic; inherent. Contrast transcendental.

immanent justice: the belief in a natural force that enforces a moral universe. The concept of karma is exemplary.

immediate early gene: genes which are instantly activated in response to cellular stimuli.

immune system: a biological system that wards against disease, especially infection. For macrobes, an immune system acts as a microbiome management system. See innate immune system, adaptive immune system.

Impatiens frithii: a small, inconspicuous epiphyte when not displaying its bright red flowers; endemic to Cameroon.

impecunious: impoverished.

imperialism: a state acquiring the territory of another nation. Compare colonialism.

imprinting (genetics): an epigenetic inheritance mechanism, where the gene expression of specific alleles is silenced based upon the sex of the parent gene set. Imprinting involves methylation and histone modifications.

imprinting (psychology): an early-instilled, rapid learning process that establishes a behavior pattern based upon identification of a certain object. The best-known imprinting is the filial devotion seen in a chick that follows its mother. Douglas Spalding discovered imprinting in chickens in the early 1870s.

impulse: an urge driven by the subconscious.

in toto: entirely; as a whole.

in vivo (Latin for “within the living”): something within an organism. Contrast ex vivo.

in-group: a group generally viewed positively. Contrast out-group. See reference-group.

incest: a sex act between a parent and an offspring or between siblings.

inclusive fitness: the hypothesis of an evolutionary strategy whereby conspecifics altruistically help one another. See kin selection.

incus (aka anvil): the anvil-shaped medial ossicle vibrated by the malleus, which then transmits the vibe to the stapes.

indehiscent: not dehiscent.

independent variable: a variable that represents an input into a function. Contrast dependent variable.

India: the 7th-largest country (3.3 million km2), with 1.3 billion people (2018); on its own subcontinent in central southern Asia. India is an ancient civilization that once was a font of spiritual wisdom that has since gone dry, at least where governance is concerned. India has a rapidly growing population matched by a rapidly deteriorating natural environment. The former won’t last long but the latter will linger for centuries.

Indian pipe (aka ghost plant, corpse plant, Monotropa uniflora): a mycoheterotrophic plant native to the temperate regions of North America and eastern Asia. The Indian pipe is white, as it lacks chlorophyll.

Indian snakeroot (aka devil pepper, serpentine wood, Rauvolfia serpentine): a flowering plant in the milkweed family, native to the Indian subcontinent and East Asia to Indonesia.

indigenous: naturally occurring in an environment or biome. Compare native, endemic.

indigobird: a brood parasitic finch native to sub-Saharan Africa.

indirect reciprocity: cooperation or altruism between 2 people who may not meet again.

individuation: a method for distinguishing an object or event from a category.

indole (C8H7N): an aromatic biocompound produced by bacteria as a degradation product of the amino acid tryptophan (C11H12N2O2).

induction (logic): the method of inferring a generalized conclusion from particulars. Contrast deduction.

Indonesia: a nation comprising over 13,000 islands in Oceania.

inductivism: the traditional scientific method of evolutionary theory formation via fact accumulation; stated by Francis Bacon in 1620, who proposed incrementally (in terms of scale) proposing natural laws to generalize observed patterns. Disconfirmed laws are discarded.

In 1740, David Hume noted limitations in using experience to infer causality. 1st is the illogic of enumerative induction: unrestricted generalization from specific instances to all such events. 2nd is the presumptiveness of conclusively stating a universal law, since observation is only of a sequence of perceived events, not cause-and-effect. Nonetheless, Hume accepted the empirical sciences as inevitably inductive.

Alarmed by Hume, Immanuel Kant posited rationalism as favored by Descartes and by Spinoza. Kant noted that the mind serves to bridge the human experience with the actual world, with the mind creating space, time, and substance. With this, Kant trashed the naïve realism of science as only tracing appearances (phenomena), not unveiling reality (noumena). Compare falsifiability.

Indus Valley: the plain in what is now western India & Pakistan.

Indus Valley Civilization (aka Harappan civilization) (~7,000–~1500 BCE): a peaceful, prosperous civilization that flourished in the basins of the monsoon-fed Indus River, extending from northeast Afghanistan to northwest India. At its peak, the civilization may have had a population of over 5 million.

Industrial Revolution: the era of industrialization that began in England in the mid-18th century. English economic historian Arnold Toynbee popularized the term in describing England’s economic development from 1760 to 1840. Industrialization engendered 3 complementary social dynamics: 1) rapid urbanization, 2) a population boom, and 3) the destruction of the existing social hierarchy headed by landed aristocracy, which was gradually replaced by a dominant social class of wealth inherited or made from manufacture, finance, and/or trade.

industrialism: a societal economic organization built largely on mechanized industry rather than agriculture and craftsmanship.

industry (archeology): a collection of contemporaneous artifacts indicting a level of technological accomplishment.

inertia: resistance to a change of motion.

inertial reference frame: a frame of reference that describes time and space uniformly (homogeneously and isotopically), and in a time-independent manner. Conceptually, the physics of a system in an inertial frame that is self-contained, with no external causes.

infantile amnesia (Freudian psychoanalytic theory): repression the earliest sexual or evil memories.

inference: the process of deriving a conclusion from premises known or assumed true.

inferential statistics: the discipline of drawing predictive conclusions from a sample. Contrast descriptive statistics.

inferiority complex: a 1927 hypothesis by Alfred Adler that a psychological sense of inferiority, even unconsciousness, warps mentation and behavior to compensate. Modern parlance prefers “lack of covert self-esteem.”

infidel: non-believer.

infinitesimal (mathematics): something so tiny that there is no way to measure it.

infinitesimal calculus (aka differential calculus): calculus of marginal change. Descartes was especially interested in tangents to curves as an extension of analytic geometry.

infinity (∞): the idea of something unlimited. Mathematics often treats ∞ as a special number, but that is a conceptual error. Infinity is beyond numerics.

inflammation: a complex biological response in vascular tissues to injury or infection, involving heat, pain, redness, swelling and loss of function, to promote healing.

inflation (economics): an increase in the general price level. From a monetary view, a lessening of a currency’s purchasing power. Contrast deflation. Compare hyperinflation.

inflationary energy: a hypothetical energy force of dense, intense negative pressure that allowed cosmic inflation.

inflaton (astrophysics): a hypothetical quantum particle (scalar field) of inflationary energy. No scalar fields have been observed in Nature. There is no evidence for the existence of inflatons.

inflorescence: a cluster of flowers on a stem.

inflorescence meristem: meristematic cells that produce floral meristem, from which flower parts develop: sepals, petals, stamens, and carpels.

influence (noun): the act of producing an effect indirectly.

influence (verb): to affect or alter, typically by indirect or intangible means.

influenza (aka the flu): an infectious disease caused by an RNA-based influenza virus.

information: an esteemed apprehension of an order among concepts.

information theory: a theory related to mathematical content quality in communication.

infotainment: entertaining information.

infrared (IR): electromagnetic radiation between 1–400 THz (terahertz). Most thermal radiation at room temperature is infrared. Infrared is emitted or absorbed by molecules when they change their rotational or vibrational mode.

infrasound: sound at a frequency lower than can be heard by human ears.

infructescence: the fruiting stage of an inflorescence (flower).

inheritance (object-oriented programming): the incorporation by a class of behaviors of an explicitly related class, typically a superclass.

inhibitor (chemistry): an enzyme that decreases reaction rate. Contrast activator.

inmind: the intuitive part of the mind. Compare demind, ramind.

innate immune system: the non-learning portion of the immune system, common among multicellular eukaryotes, including plants, fungi, and animals. Compare adaptive immune system.

inquiline: an animal that lives commensally in the dwelling of another species. The most diverse types of inquiline are found in the nests of social insects, especially ants and termites, where a single colony may support dozens of different inquilines. Inquiline is a somewhat slippery term. Parasites are by definition deleterious to their hosts. In contrast, inquilines gain from their host association, by taking advantage of host services and facilities, but do not necessarily bring their hosts down.

inquisitorial system: a judicial system where the court actively investigates the facts of cases. Contrast adversarial system.

intellectual property: granted governmental protection to cerinsect: an arthropod with a tripartite body (head, thorax, and abdomen), a chitinous exoskeleton, 3 pairs of jointed legs, a pair of compound eyes, and a pair of antennae. Insects are among the most diverse groups of animals, with over a million known species.

insectivore: an insect eater.

insertion (genetics): a mutation via inserting 1 or more nucleotides. Contrast deletion.

insomnia: abnormal inability to get enough sleep.

instinct: precocious knowledge.

institution: a structured behavior pattern accepted as part of a culture (e.g., marriage); a purposeful group or organization (e.g., the judiciary).

institutional fact: see social fact.

instrumental leader (aka task-oriented leader): a leader who tries to keep a group working toward its goals. Contrast expressive leader.

instrumentalism: the premise that a theory need not reflect reality, but merely serve as a tool for predicting the future. Contrast scientific realism.

insula (aka insular cortex, insular lobe; plural: insulae): a portion of the cerebral cortex in each hemisphere of the mammalian brain. Insulae are physiologically involved in states of consciousness.

insulator (chemistry): a medium that resists the flow of electrical current. Contrast conductor, resistor.

insulin: a hormone produced by beta cells in the pancreas that helps regulate carbohydrate and fat metabolism in the body. Insulin causes cells in skeletal muscles and fat tissue to absorb glucose from the blood. Insulin is cosecreted with amylin in a ~100:1 ratio (insulin:amylin). See amylin.

integer: a positive or negative non-fractional number, or zero.

integrase (retroviral integrase): an enzyme made by a retrovirus that enables its genetic material to be incorporated into the DNA of an infected cell.

integrated circuit (IC): a set of electronic circuits in a small semiconductor package (chip).

intein: a self-splicing protein segment which can excise itself from a larger protein molecule and rejoin a polypeptide chain (extein) via a peptide bond.

Intel Corporation (1968–): an American manufacturer of computer components, notably microprocessors.

intellectual property: granted governmental protection to certain abstractions, notably creative works (copyright), commercial brand names (trademark) and technical inventions (patents).

intelligence: an attribution for behaving appropriately; the process of gathering and analyzing information.

intelligence (tissue): 1 of the 4 primary animal tissue types. Glia and neurons are the primary cell types of intelligence tissue. See also epithelium, muscle, and connective tissue.

intelligence system: the energetic and physiological system for information collation and analysis (mentation).

intelligent design: a Christian creationist argument for the existence of God by claiming that evolution is an existence proof for a supernatural creator. The term intelligent design dates to the term’s insertion into a 1989 American high school biology textbook, but the theological argument had been in circulation at least since Thomas Aquinas’ presentation in the mid-13th century. Acceptance of evolution was not a Christian controversy until the 1920s, when a schism developed in the Presbyterian church between a conservative fundamentalist movement and a more modernist wing. (American Presbyterianism had been rocked by doctrinal divisiveness twice before, in the early 1740s and in the mid-1830s.) In the 1930s, this doctrinal split infected other Protestant denominations, and the Catholic Church. By the end of the 1930s, the modernists had prevailed. But the fundamentalists had their say in a very public way by having the teaching of evolution effectively suspended in US public schools until the 1960s, when evolution was reintroduced. Fundamentalists then argued to have creationism taught as an alternative theory, but were rebuffed by the US courts, where their effort ended up. The US Supreme Court ruled in 1987 (in Edwards v. Aguillard) that creationism violated the Constitution’s 1st amendment against the state advancing a particular religion. Creationism found similar disapproval in Europe. Undeterred, creationists immediately took to intelligent design, which posits evolution as prudently designed. Aware of the obvious blowback, proponents soft-pedal the supposed supreme being behind the curtain of intelligent design. Rather subtle sophistry has evolved to buttress the idea of intelligent design, including irreducible complexity, specified complexity, and a fine-tuned universe. These intelligent design theories are as decent as most scientific theories, which are nothing more than religious dogma backed only by selective data, aiming at an ulterior perspective (for example, neurobiologists absurdly advocating the brain as the source of mentation).

intend (verb): to construe in a certain way.

intensive property (aka bulk property): a physical property of a system that does not depend upon system size or materiality. Examples include temperature, density, hardness, and refractive index. Richard Tolman introduced the terms intensive property and extensive property in 1917. Contrast extensive property.

intent: volition; willfulness.

interaction (physics): see force.

interactional synchrony: matching body postures and movements among people engaged in interpersonal interaction.

interactional time: coordinated time for interpersonal interaction.

interconnection: mutual connection.

interdependence: a system where one feature dynamic may affect another.

interest (finance): a periodic amount paid for holding a debt instrument, such as a loan. See principal.

interest (psychology): the consumption of attention.

interface: the boundary between phases or systems.

interferometry: a measurement technique for fields via superimposing one wave upon another to extract information about the target wave.

interferon: a protein made and let loose by a host cell in response to detecting a pathogen.

intergenic: a DNA sequence located between genes.

interglacial: a period of warmer climate within an ice age. Compare glacial period.

internal combustion engine: an engine with working cylinders in which combustion occurs within the cylinders, providing mechanical power.

Internal Revenue Service (IRS): US federal tax collection agency.

International Monetary Fund (IMF) (1944–): an international organization tasked with goals oriented toward stable capitalist economic growth. The IMF was ironically born from the understanding that capitalism is inherently instable. Funded by member contributions through a proportionate quota system, the IMF acts as a lender of last resort to countries in dire straits. Most countries in the world belong to the IMF, though relations are sometimes touchy: Argentina, for example, refuses to let the IMF monitor its finances. Nonmembers include Andorra, Columbia, Cuba, Liechtenstein, Monaco, Nauru, North Korea, Taiwan, and Venezuela.

International Office of Public Health (1907–1948): a Paris-based European public health organization, absorbed into the World Health Organization when it was founded.

internationalism: the principle of inclination toward international cooperation as promoting the common good, irrespective of nationality. Contrast nationalism.

Internet (1983–): a global computer network that evolved from arpanet which now hosts the World Wide Web.

internode (botany): growth between an established plant and its nascent offspring during vegetative reproduction.

interphase: the period of the cell cycle during which a cell lives its everyday existence. Interphase is 90% of a cell’s life cycle. See anaphase, telophase.

interplanetary magnetic field: the solar magnetic field, carried with the solar wind out into the solar system.

interspecies: between species. Contrast conspecific.

interspecific: occurring between distinct species. Contrast conspecific.

intimacy: a loving, empathic act within an emotionally close relationship.

intonation: the pattern of pitch (melodic) changes in speech.

intrinsic motivation: desire originating within oneself. Contrast extrinsic motivation.

introject: to incorporate subconsciously.

introgression (genetics): introduction of genes from one species into another.

intron: a polynucleotide sequence in a nucleic acid that does not code for protein synthesis. Introns are removed before translation of messenger RNA. Compare exon.

introspection (aka metacognition): awareness of cognition; (the capability of) reflectively examining one’s own thoughts and feelings. Compare mindfulness.

introversion: the state of being with predominant interest in one’s own mental self. Introversion and extraversion are conceptual poles of a continuum of personal psychology developed by Carl Jung in 1913, albeit its usage now is distinct from his original intention. In between introversion and extraversion is ambiversion. Contrast extraversion.

intuition: direct apprehension. Contrast phenomenon.

invasive species: a non-native species introduced into a new ecosystem.

inverse-square law: Isaac Newton’s formulation of gravity as a force: that the gravitational attraction between 2 objects is directly proportional to the product of their masses, and inversely proportional to the square of the distance between them.

inversion (genetics): a mutation by rearranging a gene sequence. Compare translocation.

invertase: an enzyme that catalyzes the hydrolysis (breakdown) of sucrose (C12H22O11) into fructose and glucose (both C6H12O6). Bees biosynthesize invertase, as do yeast.

invertebrate: an animal that is not a vertebrate. Arthropods are the best-known invertebrates.

interpreter (software): a software program that sequentially (statement by statement) translates source code in executable code and executes (runs) it. Compare compiler.

Investiture Controversy: a conflict between church and state in medieval Europe during the 11th–12th centuries; began between Emperor Henry IV and Pope Gregory VII; ended in 1122 (the Concordat of Worms), when Emperor Henry V and Pope Calixtus II agreed to a Gelasian compromise on whom bishops owed their allegiance to.

iodine (I): the element with atomic number 53. Iodine is never naturally found uncombined. It is sparingly present in seawater as an ion: ~50 mg per tonne.

ion: an electrically charged subatomic particle, atom, or molecule. See anion and cation.

ion channel: a chemical communication pathway comprised of pore-forming proteins that establish and control voltage gradients across the plasma membranes of cells by allowing the flow of ions down electrochemical gradients.

ion channel: a chemical communication pathway comprised of pore-forming proteins that establish and control voltage gradients across the plasma membranes of cells by allowing the flow of ions down electrochemical gradients.

Ionia: an ancient region of central coastal Anatolia, now Turkey. Ionia was the furthest eastern extent of ancient Greece.

ionic bond: an electrostatic attraction resulting in 2 oppositely charged ions coupling. An anion and a cation join in an ionic bond.

ionic lattice: a lattice-like structure conducive to electrical conductivity.

ionization: the energetic process of converting an atom or molecule into an ion.

ionization energy (potential): the energy required to remove an electron from a gaseous atom or ion.

ionosphere: the ionized portion of Earth’s upper atmosphere, at 85–600 km altitude.

iPhone (2007–): a portable touchscreen phone/computer made by Apple Computer.

ipso facto: by the fact itself; inherent in the very nature of the situation.

Iran: a Muslim nation in western Asia, 1.6 million km2, with 81.8 million people (2018); home to one of the world’s oldest civilizations. Iran’s main neighbor to the west is Iraq. { Spokes 6 }

Iran: an oligarchic Shiite Islamic state in the Middle East with a rich historic legacy. { Spokes 7 }

Iran–Iraq War (1980–1988): a war started by Iraq against Iran, following a long history of border disputes. The war was essentially a Muslim religious dispute. Sunni-led Iraq was worried that Shia-majority Iran would inspire insurgency among Iraq’s long-repressed Shia majority. So, Iraq attacked Iran, hoping to take advantage of the supposed chaos in the wake of the 1979 Iranian Revolution. Iraq’s offensive was quickly repelled, and the country spent the rest of the war on the defensive. The war ended with both sides exhausted.

Iraq: a Muslim nation in western Asia, 437 thousand km2, with 39 million people (2018). The alluvial plain region is historically known as Mesopotamia. Iraq’s neighbor to the east is Iran. { Spokes 6 }

Iraq: the Western cradle of civilization (from ~10,000 BCE), now a failed state in the Middle East. { Spokes 7 }

irrational number: a real number with a decimal representation that does not terminate nor repeat. Contrast rational number.

iridescence (aka goniochromism): a change of color appearance in a material based upon angle of view or illumination. Iridescence is often created via structural coloration (microstructures which create light interference patterns).

iridoid: a defensive secondary metabolite produced by plants, typically as a glycoside.

iridophore: an iridescent chromatophore; a light-reflecting pigmented cell.

iris (physiology): the thin, circular structure in an avian or mammalian eye which controls the diameter of the pupil, thus determining the amount of light reaching the retina.

Irish elk (aka Irish giant deer, Megaloceros giganteus): one of the largest deer that ever lived, which went extinct ~7,700 years ago. Its range extended across Eurasia during the Pleistocene, from Ireland to Siberia and China.

iron (Fe): the element with atomic number 26; a metal. Iron is the most common element (by mass) in Earth, forming much of its core.

Iron Age (~1300–500 BCE): the last (3rd) principal period of the 3-age system, noted for widespread use of iron and the development of steel. See Stone Age, Bronze Age.

iron-sulfur world (theory): a theory developed by Günter Wächtershäuser that life originated in seabed hydrothermal vents, nestled in pyrite.

irreducible complexity: the idea that biological systems cannot have come into being through piecemeal evolution because their inherent complexity is entangled, and thereby necessarily irreducible; hence, evolutionary incrementalism is impossible. Introduced by Michael Behe in 1996.

Irukandji jellyfish (Carukia barnesi): a small, extremely venomous box jellyfish native to the waters near Australia.

Isha Upanishad: a short Upanishad comprising prose mantras.

Islam (religion) (aka Muhammadanism): the religious system founded by Muhammad and informed by the Koran, with the basic principle of absolute submission to the god Allāh.

Islam (sociology): the societies predominantly practicing Islamic religion.

Islamic Golden Age (8th–13th century): the period in Islamic history when scientific and cultural development flourished; brought to an end by dogmatic, reactionary clerics.

Islamic State (IS): an extremist Islamic terrorist group.

Islamism: an ideology embracing the Islamic religion and emphasizing implementation of Sharia (Islamic law).

isochronism: equal or uniform in time.

isoform: functionally similar proteins with a similar (but not identical) amino acid sequence which had been encoded by different genetic instruction sets.

isolation effect: a bias introduced via the method of attribute decomposition in comparing alternatives.

isomer: a compound in one of various molecular structures (shapes). Isomers with the same chemical formula may have quite different properties.

isometric: relating to or characterized by equality of measure.

isopod: a crustacean with a rigid, segmented exoskeleton, including woodlice and sea slaters. Isopods lack a carapace (dorsal (upper) section shell) and have a special pouch for brooding eggs (which characterizes peracarid crustaceans).

isoprene (2-methyl-1,3-butadiene (C5H8)): a colorless, volatile, organic liquid produced by many plants; polymers of isoprene are the main component of natural rubber.

isotocin (C41H63N11O12S2): a peptide hormone which regulates sociability in fish; functionally like oxytocin in humans.

isotope: a variant of a chemical species. Isotopes vary by number of neutrons in the nucleus.

isotropic: the same in all directions. Compare homogeneous.

Israel: the Jewish-led nation in the Levant, founded in 1948 by Jewish takeover of land specified by the United Nations in 1947 for both an Arab and a Jewish state. Israel is a thin slice of a country, 21 thousand km2, with 8.4 million people (2018).