Combination of hilarious and helium. Meaning something that is extraordinarily funny, causing laughter and giggles. Hilarium fills the semantic void for something that is that that funny.
An adjective defining an instance where something is so funny it needs a rhyming catch phrase.
"Hey did you see that new movie? That shit was hilarium aquarium." "Did you see when that girl tripped while wearing those tall stilettos? Yeah bro, totally hilarium aquarium"
Name of a transuniversial time hopping exgladiator. General of the DXXV Legion the hammer of the Celts. Margrave di Cuisine. Chef di Cuisine aboard the A.S.S. Titalus. Le Bron Chef of renown across the verses.
To be used as an adjective.
Popular use "Those are some Gorgias Hilarius brownies!"