Young men and women drinking vodka heartily (7)
I believe the answer is:
laddies
'young men' is the definition.
(I've seen this before)
'women drinking vodka heartily' is the wordplay.
'women' becomes 'ladies' (lady is a kind of woman).
'drinking' means one lot of letters goes inside another.
'heartily' indicates the central letters.
The middle letter of 'vodka' is 'd'.
'ladies' going around 'd' is 'LADDIES'.
'and' acts as a link.
(Other definitions for laddies that I've seen before include "young men" , "Boys" .)