Drunk circling about later this evening (7)
I believe the answer is:
tonight
'later this evening' is the definition.
(I've seen this before)
'drunk circling about' is the wordplay.
'drunk' becomes 'tight' (slang term).
'circling' means one lot of letters goes inside another (circling can mean going around or containing).
'about' becomes 'on' (as in a book 'on' a certain topic).
'tight' enclosing 'on' is 'TONIGHT'.
(Other definitions for tonight that I've seen before include "On tight (anag.)" , "next retirement occasion" , "What follows today" , "Got thin (anag)" , "Later this evening" .)