Examples with it in use:

This is Pete, my known.

We've been knowns since highschool.

My known Jazmine is pretty cool.

“Okay so there was a total ten out of ten hottie on the flight back into LAX today and he asked me if I had any places to go out to recommend once I told him this was my base and I told him he just had to go here,” Frankie said, the words all coming out in one rush of air before she took a deep inhale. “True? No, not at all. But it is convenient to my house and after a three day trip, I needed convenience, but also a solid opportunity to try to hit on him when, you know, off the clock and therefore totally allowed,” she explained before shrugging up her shoulders, drink somehow already in hand despite the fact she had been at the bar for, like, two minutes flat. “But anyways, come sit with me, people watch, do some shots. But if he shows up, I will be expecting you to mysteriously disappear into the night, conveniently leaving a barstool open.”