entomology (n.)

"the branch of zoology which treats of insects," 1764, from French entomologie (1764), coined from -logie "study of" (see -logy) + Greek entomon "insect," neuter of entomos "cut in pieces, cut up," in this case "having a notch or cut (at the waist)," from en "in" (see en- (2)) + temnein "to cut" (from PIE root *tem- "to cut").

Insects were so called by Aristotle in reference to the segmented division of their bodies. Compare insect, which is from a Latin loan-translation of the Greek word. Related: Entomological; entomologically. Hybrid insectology (1766, from French insectologie, 1744) is not much used.

I have given the name insectology to that part of natural history which has insects for its object; that of entomology ... would undoubtedly have been more suitable ... but its barbarous sound terryfy'd me. [Charles Bonnet's English translation of his "Contemplation de la nature," 1766]
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entomologist (n.)

"one versed in or engaged in the study of insects," 1771; see entomology + -ist.

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entomolite (n.)

"fossilized insect," 1813, from entomo-, from Greek entomon "insect" (see entomology) + -lite "stone." Late 18c. in French and German.

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entomophagous (adj.)

"insectivorous," 1800, from entomo-, from Greek entomon "insect" (see entomology) + -phagous "eating."

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also *temə-, Proto-Indo-European root meaning "to cut."

It forms all or part of: anatomy; atom; contemplate; contemplation; diatom; dichotomy; -ectomy; entomolite; entomology; entomophagous; epitome; phlebotomy; temple (n.1) "building for worship;" tmesis; tome; -tomy; tonsorial; tonsure.

It is the hypothetical source of/evidence for its existence is provided by: Greek temnein "to cut," tomos "volume, section of a book," originally "a section, piece cut off;" Old Church Slavonic tina "to cleave, split;" Middle Irish tamnaim "I cut off," Welsh tam "morsel."

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insect (n.)

c. 1600, from Latin (animal) insectum "(animal) with a notched or divided body," literally "cut into," noun use of neuter past participle of insectare "to cut into, to cut up," from in- "into" (from PIE root *en "in") + secare "to cut" (from PIE root *sek- "to cut"). The Latin word is Pliny's loan-translation of Greek entomon "insect" (see entomology), which was Aristotle's term for this class of life, in reference to their "notched" bodies.

First in English in 1601 in Holland's translation of Pliny. In zoology, in reference to a class of animals, 1753. Translations of Aristotle's term also form the usual word for "insect" in Welsh (trychfil, from trychu "cut" + mil "animal"), Serbo-Croatian (zareznik, from rezati "cut"), Russian (nasekomoe, from sekat "cut"), etc. Insectarian "one who eats insects" is attested from 1893.

Among the adjectival forms that have been tried in English (and mostly rejected by disuse) are insectile (1620s), insectic (1767), insective (1834), insectual (1849), insectine (1853), insecty (1859), insectan (1888).

It is curious that in the eyes of the Anglo-Saxon naturalists, the frog, the toad, the lizard or eft (efte), and other reptiles, were usually placed under the head of insects ; and this odd classification was preserved to rather a late period. [Thomas Wright, "Anglo-Saxon and Old English Vocabularies," 1884]
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cursorial (adj.)

1824, "fitted for running," from Late Latin cursorius "pertaining to running" (see cursory) + -al (1). Entomology in a similar sense uses cursorious (by 1829).

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metabolism (n.)

1878 in the physiology sense of "the sum of the chemical changes within the body by which the protoplasm is renewed, changed, or prepared for excretion," from French métabolisme, from Greek metabole "a change," from metaballein "to change," from meta "change" (see meta-) + ballein "to throw" (from PIE root *gwele- "to throw, reach"). The word also has been used in theology, poetics, and entomology.

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septemdecimal (adj.)

"of seventeen years," 1855, originally and usually in reference to cicadas, from Latin septemdecim "seventeen" (see seven, ten) + -al (1). Related: Septemdecimally. Septemdecenary "occurring once in 17 years," also of cicadas, is attested by 1843 (in William Kirby and William Spence, "An Introduction to Entomology," an etymology/entomology contact).

They never descend very deeply into the earth, but remain about the tender fibres of the roots. The only change they appear to undergo in their subterranean pilgrimage of seventeen long years is increase of size. As the time of their transformation approaches, they rise to near the surface of the earth, form cemented cells, in which they pass their pupa state, after which they burst the skin on the back and ascend the first tree, and again perform their septemdecimal offices of generation. [John Hooper, report on the seventeen-year locust, in "Annual Report of the American Institute," New York, 1855] 
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boll (n.)

Middle English bolle, from Old English bolla "bowl, cup, pot, round vessel for containing liquids," merged from 13c. with Middle Dutch bolle "round object," both from Proto-Germanic *bul-, from PIE root *bhel- (2) "to blow, swell." Influenced in meaning by Latin bulla "bubble, ball" (see bull (n.2)).

The sense was extended c. 1500 to "round seed pod of flax or cotton." Boll weevil, which damages cotton bolls, is so called from 1895, American English.

In south Texas, among Spanish-speaking people, the insect is generally known as the 'picudo,' a descriptive name which refers to the snout or beak of the insect. English-speaking planters generally referred to the insect at first as 'the sharpshooter,' a term which for many years has been applied to any insect which causes through its punctures the shedding of the squares or the rotting of the bolls. As there are several native insects that are commonly called sharpshooters and which, though injurious, are by no means to be compared with this insect, it becomes necessary to discourage in every way the use of the word sharpshooter as applied to this weevil. The adoption of the term 'Mexican cotton-boll weevil' for the new pest is recommended. [New Mexico College of Agriculture and the Mechanic Arts Agricultural Experiment Station Bulletin No. 19, April 1896]

A case of entomology meddling in etymology.

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