Friendship that finished in calamity! (5)

I believe the answer is:

amity

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'friendship' is the definition.
(I've seen this before)

I don't understand the remainder of the clue.

(Other definitions for amity that I've seen before include "understanding" , "Cordiality" , "Accord" , "Friendliness" , "Cordial friendship" .)

I've seen this clue in the Evening Standard.

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