Wow, let rubbish corrupt mix at a party? (3,6,4)
I believe the answer is:
rub elbows with
'mix at a party?' is the definition.
I know nothing about this answer so I cannot judge whether it can be defined by this definition.
'wow let rubbish corrupt' is the wordplay.
'corrupt' indicates an anagram (a corrupted form).
'wow'+'let'+'rubbish'='wowletrubbish'
'wowletrubbish' is an anagram of 'RUB ELBOWS WITH'.
Can you help me to learn more?
(Another definition for rub elbows with that I've seen is " as wits who burble inanely - with 17a".)