Stomach failure at pool entrance (5,4)
I believe the answer is:
belly flop
'pool entrance' is the definition.
The answer and definition can be both acts as well as being singular nouns.
Maybe there's an association between them I don't understand?
'stomach failure' is the wordplay.
'stomach' becomes 'belly' (synonyms).
'failure' becomes 'flop' (flop is a kind of failure).
'belly'+'flop'='BELLY-FLOP'
'at' acts as a link.
Can you help me to learn more?
(Other definitions for belly flop that I've seen before include "Painful dive" , "Bad dive" , "Embarrassing dive" , "Inexpert dive" , "Ungainly sprawling dive" .)