Get rid of ultimately vile joke for the audience (5)
I believe the answer is:
egest
'get rid of' is the definition.
'ultimately vile joke for the audience' is the wordplay.
'ultimately vile' becomes 'e' (I can't justify this - if you can you should believe this answer much more).
'joke' becomes 'jest' (synonyms).
'for the audience' shows a homophone (sound like).
'jest' is a homophone of 'gest'.
'e'+'gest'='EGEST'
Can you help me to learn more?
(Other definitions for egest that I've seen before include "empty" , "void" .)