A test one performs with one's contact lens (the soft kind only) after cleaning, to see whether it is inside out or not-- and whether it is ready to be inserted into one's eye. The tacotest consists of the contact lens wearer placing the soft contact lens on a fingertip and attempting to bend the contact in half. If it closes on itself easily, it is right-side-out. If it springs back, it is inside out, and should be inverted before placed on the eyeball.
"My contact lens came out, I think it's inside out; should've done the TacoTest."
The female version of cock blocking. When a chick is hitting on a dude and then another chick steps in and takes over thus knocking the first chick out of the game.
I was totally trying to hook up with this dude at the club, then big ass Beatrice saw him, came over and was totally taco blocking me!