Seconder, being out of order, denied full expression (8)
I believe the answer is:
censored
'denied full expression' is the definition.
(censorship suppresses expression)
'seconder being out of order' is the wordplay.
'being out of order' is an anagram indicator.
'seconder' anagrammed gives 'CENSORED'.
(Other definitions for censored that I've seen before include "Used a blue pencil" , "Expurgated" , "Suppressed or banned" , "Suppressed as unacceptable" , "Encoders (anag) - made cuts" .)