Small and merry (5)
I believe the answer is:
elfin
'small and merry' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for elfin that I've seen before include "Delicate little" , "Little, charming and naughty" , "Pixie-like" , "Dainty" , "Like a tiny fairy" .)