Former announcer hosted Australian clerical staff (7)
I believe the answer is:
crozier
'clerical staff' is the definition.
(staff used by a bishop, ie a cleric)
'former announcer hosted australian' is the wordplay.
'former announcer' becomes 'crier' (town crier, historical announcing role).
'hosted' is an insertion indicator.
'australian' becomes 'oz' (nickname for Australia).
'crier' placed around 'oz' is 'CROZIER'.
(Other definitions for crozier that I've seen before include "A bishop's staff of office" , "Bishop's crook" .)