Energy vital if expecting cuddles (4)
I believe the answer is:
life
'energy' is the definition.
(I've seen this in another clue)
'vital if expecting cuddles' is the wordplay.
'cuddles' indicates the answer is hidden within the clue (the answer is held or cuddled by the clue).
'LIFE' is hidden within 'vital if expecting'.
(Other definitions for life that I've seen before include "The longest sentence" , "'While there's .... there's hope'" , "Maximum stretch?" , "Animation" , ""But an empty dream" (Longfellow) - "As tedious as a twice-told tale" (Shakespeare)" .)