A circular temple in Rome dedicated to all the gods, used since 609 AD as a Christian church (8)

I believe the answer is:

pantheon

(Other definitions for pantheon that I've seen before include "building that was built to honour gods" , "Temple of all the gods in ancient Greece" , "Ancient Roman temple" , "All the gods of a people or religion" , "Hall of fame" .)

I've seen this clue in The Independent.

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