'anilingus' originates from New Latin, formed from Latin 'anus' (anus) and 'lingere' (to lick), modeled after 'cunnilingus'.

'anilingus' was coined in New Latin/medical Latin by analogy with 'cunnilingus' and entered English usage in the 20th century as a clinical/technical term.

Initially, it meant ‘licking the anus,’ and this core sense has remained unchanged in modern usage.