Humpty Dumpty, for one
I believe the answer is:
egg
'humpty dumpty for one' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for egg that I've seen before include "Yolk and white in a shell" , "Hen fruit" , "Cooked breakfast staple" , "It's laid by hen" , "brick is a good one" .)