Kinky

google

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mid 19th century (in kinky (sense 2)): from kink + -y1.

wiktionary

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From kink +‎ -y.

etymonline

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kinky (adj.)

1844, "full of kinks, twisted, curly," from kink (n.) + -y (2). Meaning "odd, eccentric, crotchety" is from 1859; that of "sexually perverted" is from 1959. Related: Kinkiness.