When a pair of jeans makes a girl appear to have a penis.
A Jeanis is when a girl is wearing a pair of jeans, which consequently make it appear that she has a Penis. If you are a girl, and especially if you grew up in the 90's, then you have probably had at least one Jeanis in your life.
The area around the crotch that mimics the shape of a phallus while wearing jeans.
John: "Dude, it's not an erection, it's just my Jeanis."
George: "I spilled hot coffee on my crotch, luckily it didn't soak through my Jeanis."
Jeanis is the term for when your jeans bunch up, making you look like you have a penis.
I would love to wear these jeans, but they give me a huge jeanis...
(1)the Jeanis is something that takes shape in the front of your jeans that makes it look like you have a penis in your jeans, even if you don't (for the girls) (2) if you actually have a penis and the tiny Jeanis that occurs, makes it look bigger.
hey stacy you have a code jeanis happening you might wanna flatten that out