Liberates in cold spell, say (5)
I believe the answer is:
frees
'liberates' is the definition.
('free' can be a synonym of 'liberate')
'cold spell say' is the wordplay.
'cold spell' becomes 'freeze' (freeze is a kind of cold spell).
'say' shows a homophone (sound like).
'freeze' sounds like 'FREES'.
'in' acts as a link.
(Other definitions for frees that I've seen before include "Releases from confinement" , "Liberates" , "Delivers" .)