Kindness

wiktionary

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From Middle English kindenesse, equivalent to kind +‎ -ness.

etymonline

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kindness (n.)

c. 1300, "courtesy, noble deeds," from kind (adj.) + -ness. Meanings "kind deeds; kind feelings; quality or habit of being kind" are from late 14c. Old English kyndnes meant "nation," also "produce, an increase."