A sometimes awkward situation where someone else abruptly becomes aware that someone has a boner.

A combination between "interjection" and "erection"
Too many people are getting into a car, so some have to sit on laps. Attractive Girl sits on Guy's lap, Guy gets a boner

Girl: "Oh..!"
Guy: *cough* "Um, pardon my interection."
by vonvague December 30, 2010
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A physical interaction with another person involving an erection.
Ex1: I had a interection with him/her/them in the broom closet today.

Ex2: No one wants to have an interection with you.
by Greenie boi October 25, 2019
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The thing you get whilst looking at pornography on the internet.
Dude, turn the screen off. I'm getting a huge interection.
by Tyler Stickney May 14, 2006
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