Passion expressing how you must try to improve (6)

I believe the answer is:

ardour

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'passion' is the definition.
(I know that ardour is a type of passion)

I cannot understand how the rest of the clue works.

Can you help me to learn more?

(Other definitions for ardour that I've seen before include "Warm, passionate feeling" , "Love and enthusiasm" , "Enthusiasm or warmth of passion" , "Passionate zeal" , "Emotional warmth" .)

I've seen this clue in The Irish Times.

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