Package average egg, maybe one left aside (6)
I believe the answer is:
parcel
'package' is the definition.
(I know that package can be written as parcel)
'average egg maybe one left aside' is the wordplay.
I cannot quite see how this works, but
'average' could be 'par' (average score in golf) and 'par' is found within the answer.
'left' could be 'l' (common abbreviation) and 'l' is found within the answer.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for parcel that I've seen before include "Wrapped present" , "'Bundle, package (6)'" , "Pack" , "Wrapped container" , "One wrapped" .)