Warm husband is a moor (5)
I believe the answer is:
heath
'moor' is the definition.
(I've seen this before)
'warm husband' is the wordplay.
'warm' becomes 'heat'.
'husband' becomes 'h'.
'heat'+'h'='HEATH'
'is a' acts as a link.
(Other definitions for heath that I've seen before include "PM 1970-74" , "Place of gorse/heather" , "blasted place?" , "Edward -, former PM" , "Former prime minister" .)