An appetising drink (8)
I believe the answer is:
aperitif
'an appetising drink' is the definition.
(I've seen this before)
'an appetising drink' is the wordplay.
I cannot really see how this works, but
'an' could be 'per' (synonymous as in 'once an hour', 'once per hour') and 'per' is present in the answer.
'drink' could be 'it' and 'it' is found in the answer.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for aperitif that I've seen before include "Preliminary drink" , "Appetite stimulant drink" , "Pre-nosh tipple?" , "An alcoholic drink before dinner, an appetiser" , "Pre-meal appetiser" .)