Cold drifter full of lice, back in refuge (3,4)
I believe the answer is:
ice floe
'lice back in refuge' is the definition.
I can't judge whether this definition defines the answer.
'cold drifter full' is the wordplay.
'cold' becomes 'ice' (I've seen this before).
'drifter full' becomes 'floe' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'ice'+'floe'='ICE-FLOE'
'of' acts as a link.
Can you help me to learn more?
(Other definitions for ice floe that I've seen before include "Hazard to shipping" , "Floating sheet formed from glacier" , "Expanse of frozen water" , "Cold sheet" , "Floating mass of frozen water" .)