Apathy of the French (5)

I believe the answer is:

ennui

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'apathy' is the definition.
(thesaurus)

I cannot understand how the rest of the clue works.

(Other definitions for ennui that I've seen before include "World-weariness" , "Boredom, tedium" , "Boredom, dullness" , "Lower interest rate" , "boring" .)

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

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