Plural of ardour; multiple instances or types of intense passion or enthusiastic feelings.
British English plural of 'ardour,' from Old French and Latin 'ardor' (burning). The 'ou' spelling is characteristic of British English, which retained French spelling conventions after the Norman Conquest.
The British spelling 'ardours' with 'ou' is a leftover from when Norman French was the language of English royalty—it's like looking at a linguistic fossil from 1066.
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