Question

What does wumbo mean ?

Answer 1

Wumbo is the antonym of Mini, so it means abnormally large, or huge. Fun fact, there is a science now called "Wumbology" that studies anything that is large in nature, or anything that tends to be large. Sadly, it ended in 2003, where the chief scientist, Professor Alexander James Hurteau decided to shut it down.

Answer 2

well  but since you didn't bother actually defining "Wumbology" or anything else, I'll do so now: Wumbology: The study of all things Wumbo. Wumbo: "The opposite of Mini". Direct definition from Spongebob Squarepantsepisode 1, "Mermaidman and Barnacleboy IV": I wumbo. You wumbo.

hope this is right