Twits (5)
I believe the answer is:
asses
'twits' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for asses that I've seen before include "not the most sensible types" , "Idiots" , "Small, sure-footed animals" , "Pompous fools" , "Fools; beasts of burden" .)