Concludes friendship is constraining them (4)

I believe the answer is:

ends

I'm a little stuck... Click here to teach me more about this clue!

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

'friendship is constraining them' is the wordplay.
'ENDS' is hidden within the letters.
But, I'm not sure how the hidden word is indicated.

Can you help me to learn more?

(Other definitions for ends that I've seen before include "Destroys" , "Objectives, purposes" , "They may be made to meet!" , "Poles, aims" , "Borders" .)

I've seen this clue in The Irish Times.

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