Number imbibing drop of sherry, dry (7)
I believe the answer is:
thirsty
'dry' is the definition.
(I've seen this before)
'number imbibing drop of sherry' is the wordplay.
'number' becomes 'thirty' (thirty is a kind of number**).
'imbibing' is an insertion indicator.
'drop of' suggests taking the first letters.
The first letter of 'sherry' is 's'.
'thirty' placed around 's' is 'THIRSTY'.
(Other definitions for thirsty that I've seen before include "Gasping" , "Dry" , "Hungry" , "Feeling the need to drink" , "Ardently desiring" .)