Sarkozy's expression of boredom? (5)

I believe the answer is:

ennui

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'boredom?' is the definition.
(I know that boredom can be written as ennui)

I don't understand how the rest of the clue works.

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(Other definitions for ennui that I've seen before include "French boredom and lassitude" , "Low interest rate" , "boring" , "Boredom, tedium" , "Boredom, listlessness" .)

I've seen this clue in The Telegraph.

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