Wiktionary
vb. (en-third-person singular of: let off)
Usage examples of "lets off".
Heart held at bay behind a clamped jaw, he stops, holds his breath, raises the receiver to eye level, waits for a passing van, and lets off a third round.
The chances are the cops hear the earthquake Big Butch lets off and are coming to investigate.
The actual transformation doesn't require atomic reactors and all that jazz, once you learn how to control the mind vectors, but it always lets off one hell of a flash of light, as John can tell you.
I can well imagine that it's your dearest wish to see that unfortunate muttonheaded girl become the wife of a man who lets off stink bombs in night clubs and pinches the spoons and has had three divorces already and who, if the authorities play their cards right, will end up cracking rocks in Sing-Sing.
Perhaps after the convention, when the pressure lets off a bit -- although not even that is certain, now: Things are getting weird.