Galactose (see glucose) galea is the Latin word for "helmet," particularly one made of leather or skin. The galea aponeurotica (the latter term betrays an early confusion of connective tissue and nerves) is the tough, tendinous connection between the anterior and posterior bellies of the occipitofrontalis muscle, now called the "epicranius." It covers the scalp as a cap.
- galenical denotes a medicinal preparation
composed mainly of herbal or vegetative ingredients. The term is taken from the name of Galen (c. 129-200), a Greek physician who strongly promoted use of herbal agents in preference to those of inorganic origin. Born in Pergamum, Asia Minor, Galen gained prominence as court physician to Marcus Aurelius, a contemporary Roman philosopher and emperor. Galen adhered to the principles of Hippocrates, Plato, and Aristotle, while advancing his own pronouncements in an astonishing array of treatises on philosophy, philology, and medicine. His appeal lasted for well over a millennium, when many of his concepts were superceded by those of Paracelsus (1493-1541) in therapeutics, Andreas Vesalius (1514-1564) in anatomy, and William Harvey (1578-1657) in physiology. At least Galen got one thing right. According to Jerome Kagan (in Galen's Prophecy, New York: Basic Books, 1994), Galen correctly surmised that characteristics of human personality are largely innate. gall as a name for bile is descended from the Old English gealla, which meant the same, being probably related to geolo, "yellow.” Thus, the English word for bile seems to reflect its color. In all likelihood there was a primordial root, probably the Indo-European ghel, also indicating "yellow," that led to the Greek chole as a word for bile. There happens to be another "gall," quite unrelated to bile, which comes from the Latin galla, meaning a nut-like deformity found on plants infected by the larva of certain insects. Gallic acid, an astringent substance, was first found in a decoction of gallnuts. In Late Latin, galla became a word for tumor, particularly that which seemed to result from focal irritation. This also yielded the verb "to gall," meaning to rub harshly or repetitively so as to produce a sore. A saddle sore on either a horse or its rider can be said to result from galling. One occasionally hears the word used figuratively, as in "His rude behavior is galling." gallium is an element discovered in 1875 by Paul Emile Lecoq de Boisbaudran (1838- 1912), a French chemist. The name might be thought to come from Gallia, Latin for Gaul, i.e., France. More intriguing is the suggestion thatthe discoverer was making a play on his own name Lecoq, in French "the cock" and in Latin gallus. An isotope (67Ga) is used in scintigraphy to detect inflammatory infiltrates, galvanometer designates an instrument for determining the strength and direction of an electric current. The name comes from that of Luigi Galvani (1737-1798), a professor of anatomy at Bologna, who was fascinated by the wondrous properties of the newly discovered electricity. The story is told that one day in 1786 Galvani was working with a machine that produced static electricity, while on a nearby table lay some skinned frog legs. Through a scalpel held by an assistant, an impulse of electricity was transmitted to the frog muscle, which thereupon jerked. Galvani seized on this curious observation and expanded it into a rather fanciful theory of "animal electricity," which later was discredited. Nevertheless, Galvani went on to invent a chemical battery to release a flow of electric current, and on this his fame rests secure. By an interesting turnabout, Willem Einthoven (1860-1927), a Dutch physiologist, in 1902 invented a string galvanometer so sensitive as to detectthe electrical impulse generated in the heart, and this became the basis for modern electrocardiography, gamete designates a germ cell, either an ovum or a spermatocyte, essential to sexual reproduction. The term comes from the Greek gametes, "husband," or gamete, "wife." These, 94 ganglion gas in turn, relate to the Greek verb gamein, "to marry." The biologic usage of "gamete" was advanced by Johann Gregor Mendel (1822- 1884), an Austrian monk who gained fame as the naturalist who discovered the fundamental principles of genetics, ganglion is a near borrowing of the Greek ga[n]gglion. The Greek letter gamma is pronounced as "n" in "ng" when it appears before certain consonants, such as gamma, kappa, chi, and xi; this explains the change of Greek "gg" to "ng" in derivatives as they appear in Latin and modern languages. In Hippocratic writings ga[n]gglion was used for any small subcutaneous nodule, and this sense persists in the use of "ganglion" to refer to a tendinous cyst, such as is commonly found at the wrist. Galen, the 2nd-century Roman physician, used the term to refer to nerve complexes, which often appear as small nodes, and it is in this usage that "ganglion" has been most widely applied in anatomy, gangrene comes from the Greek ga[n]ggraina, "an eating sore ending in mortification." The Greek root verb may have been grainein, “to gnaw." The Greeks referred to the degeneration and necrosis of tissue in stages. That which led to mortification was ga[n]ggraina; the final stage of tissue death was sphakelos, an archaic term for the eventual slough of a gangrenous mass. There is a medical prefix sphacel- indicating a relation to advanced stages of gangrene, butitis rarely used, gargle is an imitative word that sounds like what it means, just as does the French gargouiller and the Greek gargarizein, "to wash the throat." A somewhat related word is "jargon," referring to an obfuscating language, such as doctors of medicine and other experts are sometimes wont to speak. The word is taken from the French jargon, which originally meant “the chattering of birds," indicating a sound, typically unintelligible, arising in the throat, gargoylism is a rare familial condition characterized by a grotesque facies, stunted and deformed body and limbs, an enlarged liver and spleen, and mental impairment. The term comes from "gargoyle," a type of rainspout affixed to the gutters of buildings of medieval architecture. Often the end of the spout was decorated with a caricature of a human or animal face."Gargoyle" refers to the function of the spout, not the face. The word comes from the French gargouille, "waterspout," which relates to the Latin gurgulio, "gullet." Incidentally, "gargantuan," an adjective describing anything of immense size, derives from Gargantua, the fictional giant created by Frangois Rabelais (1494-1553), the French humanist and author. The giant was so called because he had an enormous throat (Spanish garganta) to accommodate his huge meals. garrison syndrome refers to an adverse emotional reaction long delayed following the inciting event. An example is the emergence of debilitating grief only some time after a grave loss. As one mightsuppose, the term originated in military medicine where it was observed that mental breakdown became evident not necessarily in the heat ofbattle but rather only after a soldier was withdrawn to the comparative safety of a garrison well behind the lines. A garrison (taken from the French garir, “to defend") is a securely guarded military post, gas is such a short, simple word, one mighttake it for a primordial utterance. It is not. It was invented by Johannes Baptista van Helmont (1577-1644), a Flemish physician and naturalist, who felt called upon to distinguish between carbon dioxide in its usual state and the ultrafine disposition of water which became a vapor when exposed to cold. Later, van Helmont explained that his invention of the word was prompted by the Greek chaos, meaning "space," particularly in the sense of a rude, unformed mass. To the ancients, chaos was the disordered mass of elemental substances that existed before creation. Hesiod, a Greek poet of the 8th century B.C., wrote: Light, uncollected, through the chaos urged its infant way, Nor order yet had drawn his lovely train from out ofthe dubious gloom. This concept is echoed in the first chapter of the Book of Genesis: In the beginning God created the heaven and the earth. And the earth was without form, and void; And darkness was upon the face ofthe deep ... and God said, let there be light, and there was light.... 95 gastric genu gastric comes from the Greek gaster, "the paunch or belly." To the ancients, this could refer to any round protuberance. In modern medicalterminology, "gastric" is used only as an adjective to qualify whatever pertains to the stomach as an organ, e.g., a gastric ulcer. Also, it provides the combining form "gastr-," as in gastrectomy or gastroscopy, gastrocnemiusis the name ofthe large muscle forming the calf of the leg. Originally, the Greek gastroknemia (from gaster, "belly," + kneme, "leg”) referred generally to the calf, or "belly," ofthe lower leg. Gaussian curve (see normal) gauze as the word for a light, loosely woven fabric often used in bandages is said to have originated in the name of Gaza, a town near the eastern Mediterranean shore in what is now the oft-disputed strip of land between Egypt and Israel. The Old French term was gaze, and supposedly the fabric was imported from Gaza, butthis may be only a fabrication, gel comes from the Latin gelare, "to freeze." The Latin gelidus refers to whatever is cold or frosty. Anything liquid that "sets" into a solid on cooling is a gel. -gen is a suffix that appears at the end of a number of biomedical terms to indicate either a producer (e.g., androgen) or a product (e.g., nitrogen, a gaseous element that can be obtained from niter). The combining form is taken from the Greek gennad, "I produce"; german, "to produce"; or genos, "a descendent." gene is the biologic unit of heredity through which certain characteristics are passed from generation to generation. The term was introduced to the vocabulary of biology in 1909 by Wilhelm Ludvig Johannsen (1857-1927), a Danish botanist who was the first to distinguish genotype and phenotype (see mutation). He took the term from the Greek gennad, "I produce, I beget (ofthe father), or I bring forth (of the mother)." generic means relating to or descriptive of an entire group or class. The word is taken from the Latin genus, "a kind, sort, or type." Generic names for drugs, in distinction to proprietary names, are composed and assigned by the U.S. Adopted Names Council, formed in 1964 and jointly sponsored by the American Medical Association, the American Pharmaceutical Association, and the U.S. Pharmacopoeial Convention. Generic drugs are now usually thought of as those whose manufacture and purveyance are in the public domain, that is, not restricted by patent or purveyed under a trade name. genetics is that branch of biology dealing with the transmission of certain physical and biochemical traits of organisms from one generation to the next. The term was coined in 1906 by William Bateson (1861-1926), an English biologist and champion of Darwin's theory of evolution, (see gene) geniculate (see genu) genio- is a combining form used to designate that which pertains to the chin or, specifically, to the mandible. Thus, the geniohyoid muscle connects the mandible and the hyoid bone. "Genio-" is derived from the Greek geneias, "a beard"; in its plural the word means "the cheeks." genital as an adjective designates whatever may pertain to biologic reproduction and is a slight contraction of the Latin genitalis, "productive," which, in turn, is related to the Greek gennan, "to produce or bring forth." In the plural it can be a noun indicating, collectively, the organs of reproduction. However, even in this modern day, one usually hears of "the genitals” being called by their classical name “genitalia." genotype (see mutation) gentian sounds like an adjective but really is a noun, the name of a plant with showy blue blossoms. An extract of the root of Gentiana lutea was long used as a tonic and an antidote to poisons. The plant is said to have been named after King Gentius, who ruled over Illyria in the 2nd century B.C. and supposedly discovered the plant's useful properties. Gentian violet is an aniline dye that has nothing to do with the plant other than reproducing the color ofits flowers. The dye formerly was used as an antiseptic solution but now is used mainly as a stain for cytology, especially of bacteria. genu is the Latin word for "the knee," being related to the Greek gonu, which has the same meaning. In the brain, the genu ofthe internal capsule is the point where the fiber tracts bend. The diminutive, geniculate, refers to 96 geriatrics gland whatever resembles a little knee and has been applied to knotty or nodal structures, especially when they are shaped in a knee-like bend, as is the geniculate ganglion of the facial nerve. A related word is genuflect, meaning to bend the knee or to bow down, geriatrics is the treatment of disorders or diseases characteristic of elderly people. The term was coined by combining the Greek geron, "an old man," + iatreia, "the treatment of disease." Gerontology is a study of aging in allits aspects. The primitive Indo-European root may have been gar, "to wear away," or ger, "to mature, to grow old." From this came the Latin granum, "grain," in the sense of grain being the ripe fruit ofthe mature plant. The classical Latin grandis, "full-grown, great, aged," became favored in popular or Vulgar Latin over magnus and led to the French grande and the English "grand." This explains "grandfather" and "grandmother." germ is a derivative of the Latin germen, "a sprout, bud, or offshoot." Thus, a germinal cell is so called because it is capable of proliferating into a more mature tissue, organ, or organism. The use of "germ" in the sense of bacteria carries the idea that these minute bodies are the origin of certain diseases, a concept now firmly established but at one time disputed as "the germ theory of disease." The word also is aptly used in a figurative sense when one says, "Now that is the germ of an idea." German measles (see rubella) gerontology (see geriatrics) gestation is derived from the Latin verb gestare, "to carry or bear," and thus has been applied to pregnancy. Curiously, the Latin gestare could also mean "to carry a tale, to blab," and there are few in the bloom of pregnancy who are not anxiousto converse on their condition, -geusia is a combining form taken from the Greek geuma, "the taste of a thing." Thus, ageusia is an absence of the sense of taste, hypogeusia is a diminished sense of taste, and hypergeusia is a heightened sense of taste, while dysgeusia is an altered or perverted sense oftaste. giardiasis is a diarrheal disease ofthe intestine due to infection by the flagellated protozoa Giardia lamblia. Both the disease and the genus memorialize Alfred Giard (1846-1908), a French biologist who identified the prototypic protozoa in 1882. The name of the species lamblia is taken from that of Vilem Lambl (1824-1895), a Czech physician. giddy describes a common form of dizziness also known as light-headedness, but distinct from a true rotary hallucination (see vertigo). "Giddy” in Old English was gidig, which meant "insane." This, in turn, can be traced to the Teutonic gudo or "god." Thus, to be giddy once meant to be possessed by a god. Incidentally, our word "enthusiasm” once meant much the same thing, from the Greek enthousiasmos, which was formed from en, "in," + theos, "god.” gingiva is a direct borrowing of the Latin word for the gum of the jaws. It has been suggested that gingiva is a transposed derivative ofthe Latin gignere, "to bear or to produce," the allusion being to the observation that teeth spring from the gums. ginseng is a perennial herb first recognized and utilized in China. Its aromatic root yields a substance said to have medicinal properties, particularly as a stimulant and aphrodisiac. The term is an Anglicization of the Chinese jen shen that can be roughly translated as "image of man," seemingly an allusion to the anthropomorphic appearance of the forked root. glabella refers to the smooth area ofthe frontal bone between the superciliary arches or to the overlying smooth area of skin between the eyebrows. The term is taken from the Latin glaber, "hairless or bald." The Romans also used glaber as a fond nickname for a prepubescent slave. A related word is glabrous, meaning devoid of hair orsigns ofpubescence. gladiolus is a diminutive ofthe Latin gladus, "a sword," and is a term sometimes used for the pointed sternum or breastbone, the allusion being the same that led to "ensiform" and "xiphoid." The gladus was a short Roman sword such as that wielded by gladiators. "Gladiolus" is, and was in ancienttimes, also the name of a flowering plant, so called because ofthe shape ofits leaves. gland is a derivative of glandulus, the diminutive of the Latin glans, "a nut or acorn," a term also applied, as glans penis, to the end 97 glanders glottis of the male organ because of its shape. The Greeks referred to lymph glands as adenos, which apparently was derived from aden, a word for "acorn." Adeno- has become the combining form to designate whatever pertains to gland or gland-like structures, as in adenoid, adenopathy, adenoma, and adenocarcinoma, among other terms, glanders is mainly a disease of horses but is communicable to man. In horses the disease is featured by an eruption ofsubcutaneous or submucosal nodules (hence, the relation to the Latin glandulus, "a little nut"), which then coalesce, ulcerate, and discharge pus. In man, the disease affects both skin and lungs and, in its acute form, can result in often fatal septicemia. The causative microorganism is Pseudomonas mallei, formerly called Malleomyces mallei. Here we enter an etymological thicket. Malleomyces was the name given to what was supposed to be a genus of schizomycetes; the organisms are rods with rounded ends, hence the name incorporated the Latin malleus, "hammer or mallet,” + the Greek mykes, "fungus." The organism is now classified as a bacterium. Mallei presumably relates to the disease which was known by the ancients as a devastating affliction of horses and was called, by the Romans, malleus. This particular use of malleus can be thought to relate either to male habitus, "a bad condition," or to malleus as the term for a pole-ax used by the Romans to destroy animals, glaucoma is an almost direct borrowing ofthe Greek glaukdma, "a silvery swelling," being a combination of glaukos, "gleaming or silvery, especially of the sea," + -oma, "a swelling or tumor." The early Greeks used glaukdma to referto any condition ofdegeneration wherein the eyeball was reduced to the appearance of a silvery-green globe, such as occurred with a dense opacity of the crystalline lens. Later, a distinction was made between lenticular opacities and deeper degeneration consequent to increased intraocular pressure. "Glaucoma" came to be applied to the latter condition, glenoid refers to the shallow concavity in the scapula which serves for articulation with the humerus. "Glenoid" (with the "-oid" taken from the Greek eidos, "like"), however, originated with the Greek glenes, by which the ancients meant the eyeball. Perhaps the shiny cartilagenous concavity in the humerus suggested an appearance similar to that of the socket ofthe eyeball. glia is a near borrowing of the Greek gloia, "glue." More specifically, the neuroglia, the supporting and connective tissue that holds together the functional elements of the nervous system, was presumably looked upon as a sort of glue. A glioma is a tumor originating in glial cells. globulin is the diminutive of the Latin globus, "sphere," wherein the suffix “-in" denotes a derivative. Hence, the term "globulin" was applied in the early 19th century to the substance thoughtto originate in the "globules," i.e., the particulate cellular elements of blood. Later, with a clearer knowledge of blood chemistry, "globulin" was reserved for certain plasma proteins of high molecular weight. glomerulus is the diminutive of the Latin glomus, "a ball of yarn," related to the Latin verb glomerare, "to form into a ball." The glomerulus of the kidney, a minute ballshaped capillary tuft, was so named by Mercello Malpighi (1628-1694), the great Italian anatomist, and once called a "malpighian corpuscle." glomus is directly borrowed from the Latin (see glomerulus) as an anatomic term for an agglomeration of small arteries, veins, and neural elements that serves as a chemoreceptor responding to changes in blood content. The best known are the carotid bodies that lie in the bifurcation of the right and left common carotid arteries and respond to changes in blood pH and variations in concentration of blood gases. glosso- is a combining form descended from the Greek glossa, "the tongue." The glossopharyngeal (or ninth cranial) nerve serves the tongue and the pharynx. Incidentally, by the relation of "tongue" to language, we have glossary, a listing of specialized terms. Glossitis is an inflammation or erythema of the tongue often seen in various states of nutritional deficiency. glottis comes from glotta, the Attic variant of the Greek glossa, "the tongue." The Greeks also used their word, as we do, to mean "a voiced language," and it is in this sense that 98 glucagon goiter "glottis," in anatomy, has been applied to the vocal apparatus. Incidentally, the related word polyglot means a mixture, and sometimes a confusion, ofseveral languages. glucagon is a pancreatic hormone that increases blood glucose levels, thus opposing the action of insulin. The name is contrived by linking the Greek glukus, "sweet," + agon, "leading or driving.” glucose is a word contrived by a committee of the French Academie des sciences in a report dated 16 July 1838. The purpose was to name the principal constituentsugar ofthe grape, of starch, and of diabetic urine. The committee settled on glucose as a Gallicized transformation ofthe Greek glukus, "sweet to the taste,"