Word Origin & History
let (v.)
O.E. lætan "to allow, let go, bequeath, leave," also "to rent" (class VII strong verb; past tense let, pp. læten), from P.Gmc. *lætan (cf. O.S. latan, O.Fris. leta, Du. laten, Ger. lassen, Goth. letan "to leave, let"), from PIE *le(i)d- "to leave behind, leave, yield" (cf. L. lassus "faint, weary," Lith. leisti "to let, to let loose"). The primary sense appears to be "to let go through weariness, to neglect." Obsolete let (n.) "hindrance" is from O.E. lettan "hinder, delay," from P.Gmc. *latjanan, related to Mod.Eng. late. Slang letdown "disappointment" first recorded 1768. Let on "reveal, divulge" is from 1637; let up "cease, stop" is from 1787.