kind ‧ ness /ˈkaɪndnəs, ˈkaɪndnɪs/ BrE AmE noun
[ Word Family: adjective : ↑ kind ≠ ↑ unkind , ↑ kindly ; noun : ↑ kindness ≠ ↑ unkindness ; adverb : ↑ kindly ≠ ↑ unkindly ]
1 . [uncountable] kind behaviour towards someone:
I can’t thank you enough for your kindness.
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In everyday English, when you are thanking people for helping you, the normal phrase to use is Thanks for (all) your help . The phrase Thank you for your kindness sounds very polite and slightly old-fashioned.
2 . [countable] a kind action
do somebody a kindness
It would be doing him a kindness to tell him the truth.
⇨ kill somebody with kindness at ↑ kill 1 (16)