c. 1400, from Old French transformation and directly from Church Latin transformationem (nominative transformatio) "change of shape," noun of action from past-participle stem of transformare "change in shape, metamorphose" (see transform).
mid-14c., originally of religion, "a radical and complete change in spirit, purpose, and direction of life away from sin and toward love of God," from Old French conversion "change, transformation, entry into religious life; way of life, behavior; dwelling, residence; sexual intercourse," from Latin conversionem (nominative conversio) "a turning round, revolving; alteration, change," noun of action from past-participle stem of convertere "to turn around; to transform," from assimilated form of com "with, together" (see con-) + vertere "to turn" (from PIE root *wer- (2) "to turn, bend").
Sense of "a change from one religion to another" (especially to Christianity) is from c. 1400 in English. General sense of "transformation, a turning or changing from one state to another" is from early 15c. In reference to the use of a building, from 1921. Conversion disorder "hysteria" (attested from 1946 but said to have been coined by Freud) was in DSM-IV (1994). Conversion therapy in reference to homosexuality is by 1979.
"distorted projection or drawing" (one that looks normal from a particular angle or with a certain mirror), 1727, from Greek anamorphosis "transformation," noun of action from anamorphoein "to transform," from ana "up" (see ana-) + morphosis, from morphe "form," a word of uncertain etymology. In botany, "monstrous development of a part" (1830); in evolutionary biology, "gradual change of form in a species over time" (1852).
late 14c., from Old French transmutacion "transformation, change, metamorphosis" (12c.), from Late Latin transmutationem (nominative transmutatio) "a change, shift," noun of action from past-participle stem of Latin transmutare "change from one condition to another," from trans "across, beyond; thoroughly" (see trans-) + mutare "to change" (from PIE root *mei- (1) "to change, go, move"). A word from alchemy.
mid-15c., commutacioun, "act of giving one thing for another," from Old French commutacion "change, transformation, exchange, barter" (13c., Modern French commutation), from Latin commutationem (nominative commutatio) "a change, alteration," noun of action from past participle stem of commutare "to change, alter entirely" (see commute (v.)).
From c. 1500 as "a passage from one state to another;" 1590s as "act of substituting one thing for another."
mid-14c., representing the Greek rendition of Akkadian Bab-ilani "the gate of the gods," from bab "gate" + ilani, plural of ilu "god" (compare Babel). The Old Persian form, Babiru-, shows characteristic transformation of -l- to -r- in words assimilated from Semitic. Formerly also applied by Protestants to the Church in Rome, from the woman "arrayed in purple and scarlet" in Revelation xvii.5 ("And upon her forehead was a name written, Mystery, Babylon the Great, the mother of harlots and abominations of the earth").
mid-15c., deformacioun, "transformation, act of changing the form of," from Old French deformation and directly from Latin deformationem (nominative deformatio), noun of action from past participle stem of deformare "put out of shape, disfigure," from de (see de-) + formare "to shape, fashion, build," also figurative, from forma "form, contour, figure, shape" (see form (n.)). Meaning "deformity, disfigurement, alteration for the worse" is from 1540s.
1868, from German Entropie "measure of the disorder of a system," coined 1865 (on analogy of Energie) by German physicist Rudolph Clausius (1822-1888), in his work on the laws of thermodynamics, from Greek entropia "a turning toward," from en "in" (see en- (2)) + trope "a turning, a transformation" (from PIE root *trep- "to turn"). The notion is supposed to be "transformation contents." Related: Entropic.
It was not until 1865 that Clausius invented the word entropy as a suitable name for what he had been calling "the transformational content of the body." The new word made it possible to state the second law in the brief but portentous form: "The entropy of the universe tends toward a maximum," but Clausius did not view entropy as the basic concept for understanding that law. He preferred to express the physical meaning of the second law in terms of the concept of disgregation, another word that he coined, a concept that never became part of the accepted structure of thermodynamics. [Martin J. Klein, "The Scientific Style of Josiah Willard Gibbs," in "A Century of Mathematics in America," 1989]