Welsh male leaving pit for a drink (4)
I believe the answer is:
wine
'for a drink' is the definition.
(wine is an alcoholic drink)
'welsh male leaving pit' is the wordplay.
'welsh' becomes 'W' (abbreviation).
'male' becomes 'm' (common abbreviation).
'leaving' suggests deleting specific letters.
'pit' becomes 'mine' (mining pit).
'mine' with 'm' taken away is 'ine'.
'w'+'ine'='WINE'
(Other definitions for wine that I've seen before include "Accompaniment for women and song?" , "Alcoholic grape juice" , "Fermented grape juice" , "Drink made from grapes" , "eg Claret" .)