New husband wearing diamonds in a corner (5)
I believe the answer is:
niche
'a corner' is the definition.
('niche' can be a synonym of 'corner')
'new husband wearing diamonds' is the wordplay.
'new' becomes 'n'.
'husband' becomes 'h'.
'wearing' indicates putting letters inside.
'diamonds' becomes 'ice' (I've seen this before).
'h' going into 'ice' is 'iche'.
'n'+'iche'='NICHE'
'in' is the link.
(Other definitions for niche that I've seen before include "Chine (anag) - suitable place in life" , "Speciality" , "somewhere comfortable" , "Nook or recess" , "small specialised market" .)