Wan friend takes cover (6)
I believe the answer is:
pallid
'wan' is the definition.
(I know that wan can be written as pallid)
'friend takes cover' is the wordplay.
'friend' becomes 'pal' (pal can mean a friend).
'takes' is a charade indicator (letters next to each other).
'cover' becomes 'lid' (lid is a kind of cover).
'pal'+'lid'='PALLID'
(Other definitions for pallid that I've seen before include "Pale complexion because of poor health" , "Feeble, insipid" , "Without healthy colour" , "White in face, perhaps ill" , "Pale and wan (6)" .)