Stoneworker’s massive mother and male issue (10,5)
I believe the answer is:
monumental mason
'stoneworker's' is the definition.
(type of mason)
'massive mother and male issue' is the wordplay.
'massive' becomes 'monumental' (synonyms).
'mother' becomes 'ma' (Ma is another word for mother or mum).
'and' means one lot of letters go next to another.
'male issue' becomes 'son' (I've seen this in another clue).
'monumental'+'ma'+'son'='MONUMENTAL MASON'
(Other definitions for monumental mason that I've seen before include "One employed at a cemetery, perhaps" , "one with grave responsibilities?" , "worker in stone" , "Supplier of tablets" , "Maker of tombstones" .)