A horse given time to drink (8)
I believe the answer is:
amaretto
'drink' is the definition.
(I've seen this before)
'a horse given time to' is the wordplay.
'horse' becomes 'mare' (mare is a kind of horse**).
'given' says to put letters next to each other.
'time' becomes 't'.
'a'+'mare'+'t'+'to'='AMARETTO'
(Other definitions for amaretto that I've seen before include "Italian almond liqueur" , "Almond-flavoured liqueur" , "drink" , "Ma, rotate the almond liqueur" , "rink" .)