-trophiccomb. form

Etymology: < Hellenistic Greek τροϕικός (see trophic adj.). Compare French -trophique (formations in which are found from the early 19th cent., e.g. hypertrophique hypertrophic adj.), German -troph (formations in which, as well as in the rarer synonym -trophisch, are found from at least the late 19th cent.). Attested earliest in the second half of the 17th cent. in oligotrophic adj. and polytrophic adj., two apparently isolated early adaptations from Greek, and subsequently from the early 19th cent. in adaptations of foreign words (e.g. hypertrophic adj.). Adaptations of German adjectives in -troph are numerous in the second half of the 19th cent. Formations within English are found from the first half of the 19th cent.; early examples include allotrophic adj., paratrophic adj. Chiefly combining with first elements ultimately of Greek origin. The specific use with reference to hormones (sense 2) appears to reflect a changing interpretation of the functions of hormones, rather than a mere confusion of -tropic comb. form and -trophic comb. form (which is found in other scientific subject areas, e.g. chemistry; compare e.g. allotrophic adj. 1). The use of -trophic comb. form emphasizes the fact that hormones promote the growth of cells, i.e. an increase in their number or size, and can therefore be taken as (broadly) being related to nutrition, whereas -tropic comb. form stresses the fact that hormones stimulate the function of cells. Both views have their advocates; on the controversy concerning the use in hormone names, and 20th-cent. use, compare the following (and compare also tropic adj.³):1943 Endocrinology 33 407 The use of -tropic as in gonadotropic..reverses and confuses a clear, practical pre-established usage in the broad field of biology... -Trophic, even if not perfectly apt, is close enough in meaning and is free from confusion.1950 Lancet 2 Dec. 708/2 It is becoming current practice to speak of the action of a hormone in controlling an endocrine gland as trophic (e.g., thyrotrophic hormone..)... This is surely a misuse of words, from a confusion between trophic action..which is concerned with nutrition,..and tropism.., which connotes control... Is it too late to revert to thyrotropic..and the like?1971 Lancet 25 Sept. 701/2 For good or ill, -trophic is all but universal [in the names of hormones], though I saw corticotropic recently in a new edition of a student's biochemistry book from the States.