Past tense of 'cotton to,' meaning to become fond of or to understand and take a liking to something.
From cotton (to make friendly contact, possibly from 'cot' meaning shelter, or influenced by the softness of cotton cloth). This phrasal verb emerged in American English by the 19th century.
When you 'cotton to' someone, you're using a verb that might reference soft fabric making you comfortable, or it could come from the idea of nestling in a shelter—nobody's completely sure, but it stuck!
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