Green’s Dictionary of Slang

lay-off n.

[var. on lay-down n.]

(US drugs) a smoke of opium.

[US]F. Packard White Moll 175: I was down to Charlie’s this afternoon havin’ a little lay-off, an’–’ ‘One of these days,’ interrupted Shluker sharply, ‘you’ll go out like’ – he snapped his fingers – ‘that!’ ‘Can’t you leave the stuff alone?’.