1. Or: sixty-nine position / 69 position , a position for mutual oral-genital sex (cunnilingus or fellatio) wherein two lovers arrange themselves in opposite directions, head to tail and belly to belly, either side by side or one lover above the other. This position is used by heterosexual and homosexual couples for reciprocal oral and manual stimulation; it can be engaged in by two men who perform fellatio, two women who perform cunnilingus, or by a woman and a man one performing fellatio, the other cunnilingus.
2. An/the act mutual oral sex in that position. Performing simultaneous oral-genital sex is called 69ing (or sixty-nining); the aftermath is known as 69ed.
Etymology: Based on the similarity of the inverted positions of the partners with the numerals 6 and 9 joined together into 69; the circles representing the heads and the ends of the digits the feet.
Synonyms: double header; double marriage; flip-flop; fork and spoon; head over heels (in love); loop-de-loop; (play) hoop snake(s); p's and q's; playing hoopsnake; six-to-nine; soixante-neuf (69 in French); vice versa.
See also: 34 1/2; catch a sixty-nine; dinner beneath the bridge; linguistic exercise; route sixty-nine; thirty-nine.
(1) Bruce Rodgers. The Queens' Vernacular (1972): ' Know what the square root of sixty-nine is? Eight something.'
(2) ' I bowled a 69.' From Encyclopedia of Graffiti Robert Reisner & Lorraine Wechsler (1974).