A harsh term friends say to their friends so that they can feel superior and get their fragile friends to do whatever they're told. This is extremely annoying and hurts people deep down inside so it shouldn't be used unless you know it doesnt hurt them.
girl: Hey
Evil: why are you crying?
Girl: My life is falling apart, my boyfriend dumped me, my grades are falling and my parents hate me.
Evil: Stop being emo and suck it up, jeesh, you're depressing me.
Girl: (sniffle) sorry....
used for saying that someone has to accept a difficult or unpleasant situation even if they do not want to
You can either suck it up and be a man, or every time you get an ache and pain you can go out of the game.