Completely dismissed in audition (10)
I believe the answer is:
throughout
'completely' is the definition.
(I've seen this before)
'dismissed in audition' is the wordplay.
'dismissed' becomes 'threw out' ('throw out' can be a synonym of 'dismiss').
'in audition' indicates a 'sounds like' (homophone) clue (audition can mean hearing).
'threwout' is a homophone of 'THROUGHOUT'.
(Other definitions for throughout that I've seen before include "from start to finish" , "Everywhere" , "during the entire proceedings" , "Completely" , "all the time" .)