Hilarious is an adjective that describes something as being extremely funny, amusing or entertaining. When something is hilarious it brings joy and laughter to those who experience it, often causing tears from laughing so hard.
Usage examples
The comedian's stand-up routine had everyone in stitches; it was hilarious!
My younger brother told a hilarious joke that had me laughing uncontrollably.
We watched a hilarious movie last night; I couldn't stop laughing throughout.
At the party, our friends shared hilarious stories from their recent vacation.
The video of the baby laughing at a funny noise is absolutely hilarious.