Standard container used to hold soup (8)
I believe the answer is:
stockpot
'to hold soup' is the definition.
I can't judge whether this definition defines the answer.
'standard container' is the wordplay.
'standard' becomes 'stock' (synonyms).
'container' becomes 'pot' (pot is a kind of container).
'stock'+'pot'='STOCKPOT'
'used' is the link.
Can you help me to learn more?
(Other definitions for stockpot that I've seen before include "stew" , "Casserole" , "slow cooker?" , "Cook's vessel" , "source of many soups" .)