gigantic + enormous
“Ginormous” means really, really big. Kind of like “humongous,” which is supposedly a portmanteau of “huge” and “enormous,” but I couldn’t work it out. Merriam-Webster, considered the dictionary of American English, uses “humongous” as the definition of “ginormous.” I looked to see if the reverse was also true, but it wasn’t.
I think it’s an age-related thing whether you use “ginormous” or “humongous.” Which do you prefer?
from The Sound of One Hand Typing