Freezing, as having lifted top (5)
I believe the answer is:
'freezing' is the definition.
'as having lifted top' is the wordplay.
'as' becomes 'eg' (I've seen this in other clues).
'having lifted' shows that the letters should be reversed in order (in a down clue, letters go up).
'top' becomes 'lid' (lid is a kind of top).
'eg' reversed gives 'ge'.
(Other definitions for gelid that I've seen before include "Icy cold - glide (anag)", "Extremely cold, frozen", "Glacial".)