英语词源字典 - 在线词源网站

defibrillation (n.)[defibrillation 词源字典]: 1940, in reference to heartbeat, from de- + fibrillation "a beating in an abnormal way," especially of the muscles of the heart that contract irregularly in this condition.[defibrillation etymology, defibrillation origin, 英语词源]
defibrillator (n.): 1956, agent noun from defibrillation.
deficiency (n.): 1630s, from deficience (mid-15c.) + -cy; or from Late Latin deficientia, from deficientem (see deficient).
deficient (adj.): 1580s, from Latin deficientem (nominative deficiens), present participle of deficere "to desert, revolt, fail," from de- "down, away" (see de-) + facere "to do, perform" (see factitious).
deficit (n.): 1782, from French déficit (late 17c.), from Latin deficit "it is wanting," an introductory word in clauses of inventory, third person singular present indicative of deficere "to be deficient" (see deficient).
defilade (n.): 1828, from defile (n.) + -ade.
defile (v.): c. 1400, "to desecrate, profane;" mid-15c., "to make foul or dirty," alteration of earlier defoulen, from Old French defouler "trample down, violate," also "ill-treat, dishonor," from de- "down" (see de-) + foler "to tread," from Latin fullo "person who cleans and thickens cloth by stamping on it" (see foil (v.)).

The alteration (or re-formation) in English is from influence of Middle English filen (v.) "to render foul; make unclean or impure," literal and figurative, from Old English fylen (trans.), related to Old English fulian (intrans.) "to become foul, rot," from the source of foul (adj.). Compare befoul, which also had a parallel form befilen. Related: Defiled; defiling.
defile (n.): "narrow passage," 1640s, especially in a military sense, "a narrow passage down which troops can march only in single file," from French défilé, noun use of past participle of défiler "march by files" (17c.), from de- "off" (see de-) + file "row," from Latin filum "thread" (see file (v.1)). The verb in this sense is 1705, from French défiler.
defilement (n.): 1570s, from defile (v.) + -ment.
define (v.): late 14c., "to specify; to end," from Old French defenir, definir "to finish, conclude, come to an end; bring to an end; define, determine with precision," and directly from Latin definire "to limit, determine, explain," from de- "completely" (see de-) + finire "to bound, limit," from finis "boundary, end" (see finish (v.)). Related: Defined; defining.
definite (adj.): 1550s, from Latin definitus "defined, bounded, limited," past participle of definire (see define). Definite means "defined, clear, precise, unmistakable;" definitive means "having the character of finality."
definitely (adv.): 1580s, from definite + -ly (2). As a colloquial emphatic word, attested by 1931.
definition (n.): late 14c., "decision, setting of boundaries," from Old French definicion, from Latin definitionem (nominative definitio), noun of action from past participle stem of definire (see define).

In logic, meaning "act of stating what something means" is from 1640s; meaning "a statement of the essential nature of something" is from late 14c.; the special focus on words developed after c. 1550. Meaning "degree of distinctness of the details in a picture" is from 1889.
definitive (adj.): late 14c., from Old French definitif (12c.), from Latin definitivus "explanatory, definitive," from past participle stem of definire (see define). Related: Definitively.
deflagration (n.): c. 1600, from Latin deflagrationem (nominative deflagratio) "a burning up, conflagration," noun of action from past participle stem of deflagrare, from de- (see de-) + flagrare "be ablaze, burn" (see flagrant).
deflate (v.): 1891, in reference to balloons, coinage based on inflate. Latin deflare meant "to blow away," but in the modern word the prefix is taken in the sense of "down." Related: Deflated; deflating.
deflation (n.): 1891, "release of air," from deflate + -ion. In reference to currency or economic situations, from 1920.
deflect (v.): 1550s, from Latin deflectere "to bend (something) aside or downward," from de- "away" (see de-) + flectere "to bend" (see flexible). Originally transitive, the intransitive sense is first recorded 1640s. Related: Deflected; deflecting.
deflection (n.): also (and with more etymological propriety) deflexion, c. 1600, from Latin deflexionem, noun of action from past participle stem of deflectere (see deflect). Both forms were present 17c., but the spelling with -c- has come to predominate.
defloration (n.): late 14c., "culling of the finest passages from books," from Old French desfloracion (14c.), from Latin deflorationem "plucking of flowers," also "taking of (a woman's) virginity," noun of action from past participle stem of deflorare (see deflower). Compare also anthology. Also used in Middle English with reference to virginity from c. 1400.