Anal

google

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mid 18th century: from modern Latin analis, from Latin anus (see anus).

wiktionary

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Borrowed from Latin ānālis.

etymonline

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anal (adj.)

1769, from Modern Latin analis "of the anus;" see anus. Anal-retentive first attested 1957, in psychological jargon. Anal sex attested as such from 1966.