Egg noodle (3)
I believe the answer is:
nit
I believe this clue is a double definition.
'egg' is the first definition.
(a nit is an insect egg)
'noodle' is the second definition.
(both can mean a stupid person)
(Other definitions for nit that I've seen before include "Louse's egg; idiot" , "Cause of much head-scratching" , "Louse; fool" , "Idiot, ass" , "Foolish person" .)