An issue within a relationship that constitutes one partner breaking up with the other. Note that they do not need to be a "good" reason by society's standards, but are specific and individual to each relationship.

A deal breaker is ‘the catch’ that a particular individual cannot overlook and ultimately outweighs any redeeming quality the individual may possess.

Some aspect of a deal you make with another person (could be anything from a job offer to a relationship) that prevents you from being able to do it.

When you're facing a situation where there are catches to something, the deal breaker is that one catch that you cannot overlook and/or tolerate.

Children. Single people, you know exactly what I'm talking about.

a romantic cousin of the "shocker", the deal breaker involves delicately inserting your fist in the anus of your significant other. Also known as "5 in the stink"

The act of firmly yet romantically cramming your entire fist into your signifigant other's cornhole.This is a distant cousin of the shocker.