Annoying person (4)
'annoying person' is the definition.
(pest can mean an annoying person)
This is all the clue.
(Other definitions for pest that I've seen before include "A nuisance - step on it" , "Destructive insect or other animal" , "Annoying nuisance" , "Troublesome man or animal" , "Annoying person" .)
'annoying person' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for twit that I've seen before include "Twerp" , "Blockhead" , "dunce" , "Nincompoop" , "Taunt; fool" .)