Drinking vessel shown in the inset, perhaps (5)
I believe the answer is:
stein
'drinking vessel' is the definition.
(I know that stein is a type of mug)
'the inset perhaps' is the wordplay.
'perhaps' indicates an anagram.
'inset' with letters rearranged gives 'STEIN'.
'shown in' acts as a link.
(Other definitions for stein that I've seen before include "Inset (anag.)" , "German earthenware beer mug" , "Large earthenware beer mug" , "Beer-mug" , "Inset into earthenware mug for beer" .)