Other forms: cleavers
A cleaver is a large knife, used mainly by butchers. The blade of a cleaver is big and square.
To cut a steak, you need a good, sharp knife. To cut larger parts of meat, you need something even more powerful: a cleaver (or chopper). Cleavers have fat, square blades and are used for cutting large hunks of meat. It can help you remember the meaning of this word if you know that to cleave is to separate. If you're not a butcher, you probably have no use for a cleaver (unless you're a villain in a horror movie).