Yo Mama and the Titanic

Listen up, buttercup. This "yo mama" joke is saying yo mama so fat, she bigger than the Titanic. Now, the Titanic was a BIG boat, like, sunk-in-the-ocean-after-hitting-an-iceberg big. Saying someone's mama is bigger than that? That's a whole lotta lard. You probably think that's 'thicc'.