A bookend (5)

I believe the answer is:

finis

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'a bookend' is the definition.
Although both the answer and definition are singular nouns, I cannot understand how one could define the other.

This is all the clue.

Can you help me to learn more?

(Other definitions for finis that I've seen before include "End (of book or film)" , "conclusion!" .)

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

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