Former hamper missing in display (7)
I believe the answer is:
exhibit
'display' is the definition.
('exhibit' can be a synonym of 'display')
'former hamper missing' is the wordplay.
I cannot really understand how this works, but
'former' could be 'ex' and 'ex' is found within the answer.
This may be the basis of clue (or it may be nonsense).
'in' is the link.
(Other definitions for exhibit that I've seen before include "Put on show" , "Manifest" , "Present" , "Something on show" , "Demonstrate" .)