High point of an oratorio (3)

I believe the answer is:

tor

'high point' is the definition.

'of an oratorio' is the wordplay.
'of' indicates the answer is hidden within the clue.
'TOR' is hidden within 'oratorio'.

(Other definitions for tor that I've seen before include "Rocky prominence" , "Rot on a hill in Cornwall" , "eminence" , "rise" , "Rot on a Cornish hill" .)

I've seen this clue in the Evening Standard.

Want a hint initially instead of a full solution? Install my app