c. 1300, "to condemn, curse," also "to destroy utterly;" from Anglo-French confoundre, Old French confondre (12c.) "crush, ruin, disgrace, throw into disorder," from Latin confundere "to confuse, jumble together, bring into disorder," especially of the mind or senses, "disconcert, perplex," properly "to pour, mingle, or mix together," from assimilated form of com "together" (see con-) + fundere "to pour" (from nasalized form of PIE root *gheu- "to pour").
From mid-14c. as "to put to shame, disgrace." The figurative sense of "confuse the mind, perplex" emerged in Latin, passed into French and thence to English by late 14c. The Latin past participle confusus, meanwhile, became confused (q.v.). The meaning "treat or regard erroneously as identical" is from 1580s.
as an intensive execration, "odious, detestable, damned," 1650s, past-participle adjective from confound in its older sense of "condemn, curse," which came to be considered "a milder form of imprecation" [OED]. It is perhaps a euphemism for damned. The sense of "put to mental confusion" is recorded from mid-14c.
1550s in a literal sense "mix or mingle things or ideas so as to render the elements indistinguishable;" from mid-18c. in the active, figurative sense of "perplex the mind or ideas of, discomfit in mind or feeling," but not in general use until after c. 1800. From 1862 as "erroneously regard as identical." It took over these senses from its older doublet, confound (q.v.).
The past participle confused (q.v.) is attested much earlier, in Middle English (serving as an alternative past tense to confound), evidently an adaptation of Old French confus or Latin confusus, "with the native ppl. ending -ED and the present stem a much later inference from it" [OED]. Related: Confusing.
c. 1300, confusioun, "overthrow, ruin," from Old French confusion "disorder, confusion, shame" (11c.) and directly from Latin confusionem (nominative confusio) "a mingling, mixing, blending; confusion, disorder," noun of action from past-participle stem of confundere "to pour together," also "to confuse" (see confound).
Meaning "act of mingling together two or more things or notions properly separate" is from mid-14c. Sense of "a putting to shame, perturbation of the mind" (a sort of mental "overthrow") is from c. 1400 in English, while that of "mental perplexity, state of having indistinct ideas" is from 1590s. Meaning "state of being mixed together," literally or figuratively, "a disorderly mingling" is from late 14c.
early 15c., of persons, "to perceive, distinguish;" also, of things, "to refer to, relate to, pertain to," from Old French concerner (15c.) and directly from Medieval Latin concernere "concern, touch, belong to," figurative use of Late Latin concernere "to sift, mix as in a sieve," from assimilated form of Latin com "with, together" (see con-) + cernere "to sift," hence "perceive, comprehend" (from PIE root *krei- "to sieve," thus "discriminate, distinguish").
Apparently the sense of the first element shifted to intensive in Medieval Latin. From late 15c. as "to affect the interest of, be of importance to;" hence the meaning "to worry, disturb, make uneasy or anxious" (17c.). Reflexive use "busy, occupy, engage" ("concern oneself") is from 1630s. Related: Concerned; concerning.
Used imperatively from 1803 (compare similar use of confound); often rendered in dialect as consarn (1832), probably a euphemism for damn (compare concerned). Letter opening to whom it may concern attested by 1740.
early 14c., "discomfited, routed, defeated" (of groups), serving at first as an alternative past participle of confound, as Latin confusus was the past participle of confundere "to pour together, mix, mingle; to join together;" hence, figuratively, "to throw into disorder; to trouble, disturb, upset."
The Latin past participle also was used as an adjective, with reference to mental states, "troubled, embarrassed," and this passed into Old French as confus "dejected, downcast, undone, defeated, discomfited in mind or feeling," which passed to Middle English as confus (14c.; for example Chaucer's "I am so confus, that I may not seye"), which then was assimilated to the English past-participle pattern by addition of -ed. By mid-16c., the word evolved a back-formed verb in confuse. Few English etymologies are more confusing.
Of individuals, "discomfited in mind, perplexed," from mid-14c.; in logic, "indistinct, indistinguishable from other ideas from which it ought to be different," 1610s. Meaning "lacking orderly arrangement of parts" is from 1776. Related: Confusedly.
It forms all or part of: alchemy; chyle; chyme; confound; confuse; diffuse; diffusion; effuse; effusion; effusive; fondant; fondue; font (n.2) "complete set of characters of a particular face and size of type;" found (v.2) "to cast metal;" foundry; funnel; fuse (v.) "to melt, make liquid by heat;" fusible; fusion; futile; futility; geyser; gush; gust (n.) "sudden squall of wind;" gut; infuse; ingot; parenchyma; perfuse; perfusion; profuse; refund; refuse (v.) "reject, disregard, avoid;" refuse (n.) "waste material, trash;" suffuse; suffusion; transfuse; transfusion.
It is the hypothetical source of/evidence for its existence is provided by: Greek khein "to pour," khoane "funnel," khymos "juice;" Latin fundere (past participle fusus) "melt, cast, pour out;" Gothic giutan, Old English geotan "to pour;" Old English guttas (plural) "bowels, entrails;" Old Norse geysa "to gush;" German Gosse "gutter, drain."
"confound, confuse," 1852, a fantastical mock-Latin American English coinage from confound or confuse, originally in "Negro dialect" passages in works such as "J. Thornton Randolph's" pro-slavery "The Cabin and Parlor" (1852, a response to "Uncle Tom's Cabin"), picked up in London publications by the 1860s. Similar formations include confubuscate, conflabberated, etc., and compare discombobulate. Related: Confusticated; confusticating.