Albumen container (3)
I believe the answer is:
egg
'albumen container' 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 "Cooked breakfast staple" , "Poached or boiled?" , "It may be poached" , "Mine (slang)" , "Breakfast food, perhaps" .)