He's buried in an avalanche (4)
I believe the answer is:
alan
'he's' is the definition.
(I've seen this before)
'buried in an avalanche' is the wordplay.
'buried in' indicates a hidden word.
'ALAN' can be found hidden inside 'avalanche'.
(Other definitions for alan that I've seen before include "- Bennett, English dramatist, author" , "- Bennett, English actor, dramatist, writer" , "A.A. Milne's first name" , "Lana (anag.), man's name" , "Boy" .)