Definition: To die.

Origin: This quaint little idiom comes to us from an old-school suicide technique. A man would tie a noose around his neck, securing the other end to a tree branch or an overhead beam while he propped himself up on a bucket. When he wanted to bid adieu to the world, he would kick the bucket out from beneath himself, sending him to his maker, and no doubt leaving behind an inconvenient little mess for the maid to clean up.

Kinda morbid….

The OED describes as more plausible the archaic use of “bucket” as a beam from which a pig is hung by its feet prior to being slaughtered. To kick the bucket, then, originally signified the pig’s death throes;

Bucket is a dereveration of the word old French word buchete (meaining butcher) hence to kick the buchete – and the change into English but retation on the meaning.

A more credible explanation is given by a Roman Catholic Bishop, The Right Reverend Abbot Horne, F.S.A. He records on page 6 of his booklet “Relics of Popery” Catholic Truth Society London, 1949