define decompose
Decompose is defined as to rot, to decay, to break down into parts or to disintegrate into the earth, or to cause something to break down or rot. 1  When a dead body breaks down and eventually some of its parts disintegrate into the earth, this is an example of a time when the body decomposes. When you cause something to rot or break down, this is an example of a time when you decompose the item.