A random word that shows indifference. (In other words, you tell me about your day, I don't care but I have to say SOMETHING.. That's where yum comes in!)
Justin: I talked to Ashley today.. We got in a fight and she told me that I was worthless and a bad boyfriend and my hair is ugly and etc. etc.
Me: Yum!
A woman's nice yummy buttocks. Usually young and plump in nature. They come in all kinds of shapes and sizes. When in the field of vision of a Yum Bum it drives you wild. Almost to the point of biting your lips.
Whippersnapper: Hey Sammy, look at those delicious Yum Bums. Looks so nice I almost bit my lip.
Whipper's friend: Yes I agree, those Yum Bums are the tops.
Yuck my Yum is something you say when you're pretending to be a gay controversial figure. (ex. recently my friend said that while pretending to be kyle rittenhouse)