Captain Kidd perhaps lost his head in a rage (5)

I believe the answer is:

irate

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'in a rage' is the definition.
(I've seen this in another clue)

I cannot understand how the remainder of the clue works.

(Other definitions for irate that I've seen before include "Mad" , "Boiling" , "Extremely cross" , "Angry, annoyed" , "Wild" .)

I've seen this clue in The Globe and Mail.

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