Madcap, wacky (4)
I believe the answer is:
zany
I believe this clue is a double definition.
'madcap' is the first definition.
(I've seen this before)
'wacky' is the second definition.
(I know that wacky can be written as zany)
(Other definitions for zany that I've seen before include "old assistant clown" , "Endearingly funny" , "Comically eccentric" , "Amusingly eccentric" , "Bizarrely comic" .)