flatfishing

someone on a dating website that puts oranges in their bra to disguise the fact they're flat . Also works with someone stuffing pillows down their trousers

When a girl looks thicc in her pictures and when you meet her she's flatter than a 2x4

When your first year uni flatmates catfish you into believing they're sociable, but become boring fucks in second year.

When a student is unprepared for a class, either has not done the homework assignment or did not do the work, or maybe even forget the materials needed for the class and as a result, the student tries to lay low the entire class and not get called on by the teacher.

Flat-fishers may be seen averting eye contact with the teacher, pretending to be very focused on something in their notebook, or pretending to take notes. Overall, just trying to go unnoticed until the class is over.

a fish who is hammered with a hammer to flat it down
its squeeshed to death