cunnilingus
1887, from Mod.L. cunnus “vulva” (see cunt) + lingere “to lick” (see lick (v.)). The L. properly would mean “one who licks a vulva,” but it is used in Eng. in reference to the action, not the actor. The verb ought to be cunnilingue.
“Cunnilingue” made me realize that “lingere” is the present active infinitive form of “lingo”, a 3rd conjugation verb. This means that cunnilingus and lingo are derivatives of the same Latin verb “to lick”. Linger, however, is from the Old English “lengan”.
Etymology is fun! Learn about the origin of cunt.
Source: dictionary.reference.com
I once lived in Japan. 
