What does "kick the bucket" mean — and why is it funny?

informal, humorous

Meaning

To die.

Where it comes from

Uncertain; one theory involves a beam called a 'bucket' from which animals were hung, another the kicking away of a bucket someone stood on. The mystery is part of the appeal.

Why it is funny

It makes the most serious subject sound trivial and slightly slapstick. Death gets reduced to knocking over a household object, almost a clumsy stumble. That irreverence — treating mortality as a minor mishap — is a way of laughing at something frightening.

Used in a sentence

"He wants to see the pyramids before he kicks the bucket."