effect (n.) Look up effect at Dictionary.com
late 14c., "a result," from Old French efet (13c., Modern French effet) "result, execution, completion, ending," from Latin effectus "accomplishment, performance," from past participle stem of efficere "work out, accomplish," from ex- "out" (see ex-) + facere "to do" (see factitious).

Meaning "impression produced on the beholder" is from 1736. Sense in stage effect, sound effect, etc. first recorded 1881. The verb is from 1580s. Related: Effecting; effection.