Until the 1970s, the American faux spouse was too rare and taboo to even try to track. In 1980, the United States Census Bureau made its first attempt at naming these creatures in order to count them. It really outdid itself lexicographically: ‘person of opposite sex sharing living quarters,’ abbreviated to POSSLQ and pronounced ‘possle cue.’ The CBS commentator Charles Osgood had his way with the acronym, publishing a poem riffing John Donne’s ‘The Bait.’
You live with me, and I with you,
And you will be my POSSLQ.
I’ll be your friend and so much more;
That’s what a POSSLQ is for.