100th anniversary (9)

I believe the answer is:

centenary

'100th anniversary' is the definition.
(I've seen this before)

This is all the clue.

(Other definitions for centenary that I've seen before include "100th anniversary" , "special occasion" , "celebration" , "significant anniversary" , "One hundredth anniversary" .)

I've seen this clue in the Irish Times (Simplex), The Guardian, the Sydney Morning Herald, The Independent, The Mirror, The Telegraph and The Times.

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