Silly, annoying person (4)
I believe the answer is:
twit
I believe this is a double definition.
'silly' is the first definition.
(thesaurus)
'annoying person' is the second definition.
(I've seen this in another clue)
(Other definitions for twit that I've seen before include "Tease - fool" , "Twerp" , "Taunt; fool" , "Blockhead" , "Bait - fool" .)