Stagger, nearly attacked by a wasp (4)
I believe the answer is:
stun
'stagger' is the definition.
(both can mean to shock)
'nearly attacked by a wasp' is the wordplay.
'nearly' means to remove the last letter.
'attacked by a wasp' becomes 'stung' (I've seen this in another clue).
'stung' with its last letter taken away is 'STUN'.
(Other definitions for stun that I've seen before include "Astound; render senseless" , "Daze, scatter senses" , "Concuss, stupefy" , "Daze, stupify" , "Make senseless or dizzy with a blow" .)