A corps is an army unit consisting of at least two divisions. This word can also refer to other groups of people, like a press corps, which is a gang of journalists trying to get the scoop.
Although the word corps comes from the Latin corpus, for “body,” don’t pronounce the p or you’re talking about the kind of body that goes in a coffin. The main meaning of a corps (which is singular despite the s) is a unit of the army. The word applies to other groups, too. A law firm has a corps of lawyers, a doctor has a corps of nurses, and a tiny car could have a corps of clowns.