Show topless chest (5)
I believe the answer is:
offer
'show' is the definition.
(I've seen this before)
'topless chest' is the wordplay.
'topless' means to remove the first letter.
'chest' becomes 'coffer' (coffer is a kind of chest).
'coffer' with its initial letter taken away is 'OFFER'.
(Other definitions for offer that I've seen before include "Submit" , "Tender or propose" , "Tender, volunteer" , "Volunteer, present" , "Chance to buy at reduced price?" .)