S/he is incarcerated (8)

I believe the answer is:

prisoner

(Other definitions for prisoner that I've seen before include "One in gaol" , "One inside" , "The ---, cult 60s TV series" , "Person held captive as by law" , "'Convict, detainee (8)'" .)

I've seen this clue in the Irish Times (Simplex) and The Irish Times.

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