Ennui verging on the gloomy, nursing injured heart (6)

I believe the answer is:

tedium

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

I don't understand the remainder of the clue.

(Other definitions for tedium that I've seen before include "boring" , "'Boredom, ennui (6)'" , "Boredom, mental weariness" , "Boredom with monotony" , "Routine" .)

I've seen this clue in the Sydney Morning Herald.

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