let off verb 4let-off noun 2forms 3 verb4 •To cause to explode or come out; to release.Stand back when you let off fireworks. •To forgive and not punish.The boss let me off for breaking the office window, when in theory she could have fined me about 30 dollars. •To ease off.You let off the throttle while you're shifting, then you resume once you've caught the next gear. •Synonym of leave off. let-off noun2 •An escape from punishment.The accused received a suspended sentence, which many saw as a let-off.The missed penalty was a massive let-off for the home team. •A device for letting off, releasing, or giving forth, as the warp from the cylinder of a loom. formsletting off · lets off · let-offs