Examine end of zip on dress (5)
I believe the answer is:
probe
'examine' is the definition.
('probe' can be a synonym of 'examine')
'end of zip on dress' is the wordplay.
'end of' suggests the final letters.
'on' means one lot of letters go next to another.
'dress' becomes 'robe' (robing is a kind of dressing**).
The last letter of 'zip' is 'p'.
'p'+'robe'='PROBE'
(Other definitions for probe that I've seen before include "(Crime) investigation" , "Examine searchingly" , "Poke into" , "Investigate closely" , "Intrusive device" .)