RhymeZone: douceur definitions

Definitions of douceur:

noun: Sweetness of manner: agreeableness, gentleness.
noun: (obsolete) Sweet speech: a compliment.
noun: A sweetener: a gift offered to sweeten another's attitude, a tip or bribe.
noun: (UK) A tax break provided as an inducement to sell valuable items (especially art) to public collections rather than on the open market.

(Definitions from Wiktionary)