Workplace slang for a loose cannon, often used to discreetly signal a red flag in a consort of interest. Usually a broken person displaying bipolar and/or manic tendencies. So called because they'll switch up on you in ten seconds or less.
Tom: "Bro... someone said you were dating your client Gina."
Greg: "What?! Yeah, imagine that. Me, dating a ten second person."
A crazy person, usually in a human services setting. So called because they'll switch up on you in ten seconds.
Mary: "Did you hear about Brian and Jessica? What is he thinking with dating a client?"
Denise: "Yeah, I know about it. Let's see how long he lasts in his job, dating a ten second person."
Making someone not your first priority
Hey baby, don't be putting me on your second shut now shmucuz I wanna make you cum real quick.
When a girl dates a guy who needs therapy, so she ends up going to therapy herself. It means that motherducker is receiving second-hand therapy.
I gotta find a girl in therapy, so I can release all of my anger onto her without feeling guilty. She can just release it back onto her therapist. I ain't paying $120 an hour. I use second-hand therapy.
Second cousin's great-grandchild.
My second great-great-cousin-nibling is a good person.
Used in place of 2 seconds, when the task holding you up will take a moment, but your still trying your hardest to be quick.
Sesterple-2C: Person who, in relation to the other person, has zero parents, zero grandparents and five great-grandparents in common.
My sesterple-second-cousin is a good person.