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late 14c., "mental state," from Latin noun use of affectus "furnished, supplied, endowed," figuratively "disposed, constituted, inclined," past participle of afficere "to do; treat, use, manage, handle; act on; have influence on, do something to," a verb of broad meaning, from ad- "to" (see ad-) + facere (past participle factus) "do" (see factitious). Perhaps obsolete except in psychology. Related: Affects.
"to make an impression on," 1630s; earlier "to attack" (c.1600), "act upon, infect" (early 15c.), from affect (n.). Related: Affected; affecting.
"to make a pretense of," 1660s, earlier "to assume the character of (someone)" (1590s); originally in English "to aim at, aspire to, desire" (early 15c.), from Middle French affecter (15c.), from Latin affectare "to strive after, aim at," frequentative of afficere (past participle affectus) "to do something to, act on" (see affect (n.)). Related: Affected; affecting.
affect af·fect (ə-fěkt')
v. af·fect·ed, af·fect·ing, af·fects
To have an influence on or affect a change in.
To attack or infect, as a disease.
A feeling or emotion as distinguished from thought, or action.
A strong feeling with active consequences.