Male fowl left on top of eggs one shelled (6)
I believe the answer is:
cockle
'eggs one shelled' is the definition.
I can't judge whether this defines the answer.
'male fowl left on top' is the wordplay.
'male fowl' becomes 'cock' (cock is a kind of fowl. I am not sure about the 'male' bit.).
'left' becomes 'l' (common abbreviation).
'on' becomes 're' (regarding).
'top' means to remove the first letter.
're' with its initial letter taken away is 'e'.
'cock'+'l'+'e'='COCKLE'
'of' is the link.
Can you help me to learn more?
(Other definitions for cockle that I've seen before include "Common edible bivalve" , "Seafood item" , "Mollusc - cornfield weed" , "Edible bivalve mollusc" , "Shellfish" .)