Blocked poet, we hear (6)
I believe the answer is:
'blocked' is the definition.
(barring is a kind of blocking)
'poet we hear' is the wordplay.
'poet' becomes 'bard' (bard is a kind of poet).
'we hear' indicates a 'sounds like' (homophone) clue.
'bard' is a homophone of 'BARRED'.
(Other definitions for barred that I've seen before include "Precluded, obstructed" , "Refused access to, say pub" , "Refused entry to local pub" , "Prohibited" , "Excluded, blocked" .)