say it: hi-LER-ee-uhs
hilarious is an adjective meaning "marked by or causing boisterous merriment or convulsive laughter". It carries one recorded sense.
marked by or causing boisterous merriment or convulsive laughter
“hilarious broad comedy”
“a screaming farce”
“uproarious stories”
Definitions, synonyms and semantic relations for hilarious come from Princeton University’s WordNet. The pronunciation comes from the CMU Pronouncing Dictionary. Commonness is measured against a corpus of everyday English. Full sources and licences.