Ronald's in the ceremonial seat (6)
I believe the answer is:
throne
'ceremonial seat' is the definition.
(I've seen this in another clue)
'ronald's in the' is the wordplay.
'ronald' becomes 'ron' (I've seen this in other clues).
'in' means one lot of letters goes inside another.
'ron' placed within 'the' is 'THRONE'.
(Other definitions for throne that I've seen before include "Seat of royalty" , "Sovereign's chair" , "Seat of monarch" , "Hornet (anag) -- lavatory" , "Chair of the monarch" .)