Whisky? Macallan, Ardbeg, Lagavulin, Talisker, for starters (4)
I believe the answer is:
malt
'whisky?' is the definition.
(malt whisky is a kind of whisky)
'macallan ardbeg lagavulin talisker for starters' is the wordplay.
'for starters' suggests taking the first letters.
The first letters of 'macallan ardbeg lagavulin talisker' is 'MALT'.
(Other definitions for malt that I've seen before include "Brewing material" , "Brewing agent" , "Barley product used in brewing" , "Kind of Scotch whisky" , "Pure whisky" .)