Old cat, losing it, turned man-eater (6)

I believe the answer is:

ogress

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'man-eater' is the definition.
(I've seen this before)

I cannot understand how the remainder of the clue works.

(Other definitions for ogress that I've seen before include "Terror" , "Terrifying female" , "Female man-eating giant" , "Frightful woman" , "earsome lady" .)

I've seen this clue in The Times and The Sunday Times.

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