Lips are fixed around cold air hole (8)
I believe the answer is:
spiracle
'air hole' is the definition.
(I've seen this in another clue)
'lips are fixed around cold' is the wordplay.
'fixed' is an anagram indicator.
'around' indicates putting letters inside.
'cold' becomes 'C' (abbreviation, eg on taps).
'lips'+'are'='lipsare'
'lipsare' with letters rearranged gives 'spirale'.
'spirale' enclosing 'c' is 'SPIRACLE'.
(Other definitions for spiracle that I've seen before include "Whale's blow-hole" , "Breathing space" , "passage through rock" , "Opening" .)