Tease good-naturedly (5)
I believe the answer is:
chaff
'tease good-naturedly' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for chaff that I've seen before include "Shucks" , "twit" , "something worth little" , "Laugh at" , "Corn-husks separated from the grain" .)