A reply to something stated against you, or you're bored and say it for no reason. The meaning lies in the word itself.
Yo mama fat it flattened my thighs while sitting on me. (I used it because Yo Mama is an animal)
Yo Mama is a term that can also be written as "Your Mom". Followed by these words are usually rude adjectives/jokes to describe one's mother. But, some may choose to refer to your mother as fine or a milf by using sexual references instead of hurtful words.
Your Friend: Yo Mama so hairy when she gave birth to you, you had RUG BURNS
You: Wow man that's kinda rude
Your Friend: Sorry dude, it's just a joke
the one and only female person that gave birth to you and suffered horrible pain just so you can live and make fun of her on the internet.lmao
Yo mama so old shes on Generation A
The most unoriginal and unfunny joke in the world.
5th grader: hey guess what
6th grader: what
5th grader: yo mama
6th grader: *Beats ass sexually*
you eat my elephants uncle billy bob and then suck his dick
you yo mamaed