Astonish someone on a pre-nuptial celebration? (7)
I believe the answer is:
stagger
'astonish' is the definition.
(thesaurus)
I don't understand the rest of the clue.
Can you help me to learn more?
(Other definitions for stagger that I've seen before include "Reel - astound" , "Walk as if drunk" , "bowl over" , "Teeter" , "Reel, walk unsteadily" .)