Misty ale, burn off (7)
I believe the answer is:
nebular
'misty' is the definition.
(I've seen this before)
'ale burn off' is the wordplay.
'off' indicates anagramming the letters.
'ale'+'burn'='aleburn'
'aleburn' is an anagram of 'NEBULAR'.
(Other definitions for nebular that I've seen before include "relating to some stars" , "Hazy and formless" , "Like a cloud (in space)" , "Cloudlike" , "Cloudy" .)