Origin and history of affection

"to make a pretense of," 1660s, earlier "to assume the character of (someone)," 1590s; originally in English in a now-obsolete sense of "aim at, aspire to, desire" (early 15c.), from Old French afecter (15c.), later affecter, from Latin affectare "to strive after, aim at, aspire to," frequentative of afficere (past participle affectus) "to do something to, act on, influence" (see affect (n.)). Related: Affected; affecting.

1580s, "fond, loving," from affection + -ate (1); suggested by French affectionné. Early, now mostly obsolete, senses included "prejudiced" (1530s), "inclined" (1530s), "passionate" (1540s), "earnest" (c. 1600). Other forms also used in the main modern sense of this word included affectual "zealous; affectionate" (early 15c.), affectuous "eager, loving" (mid-15c.), affectious (1580s), from Latin affectuosus. Related: Affectionately.