Husband in drab boat (6)
I believe the answer is:
dinghy
'boat' is the definition.
(type of boat)
'husband in drab' is the wordplay.
'husband' becomes 'h'.
'in' is an insertion indicator.
'drab' becomes 'dingy' (I've seen this before).
'h' going inside 'dingy' is 'DINGHY'.
(Other definitions for dinghy that I've seen before include "Small rowing or sailing boat" , "Light rowing boat" , "craft" , "little boat" , "Small open boat, maybe a rubber inflatable" .)