Wiktionary
n. A style of comedic performance in which common and/or unusual objects are used as physical aids to help achieve a humorous effect.
Wikipedia
Prop comedy is a comedy genre in which performers use humorous objects, or conventional objects in humorous ways. The stages and films term " prop", an abbreviation of "property", refers to any object an actor handles in the course of a performance. Though some form of prop comedy has likely existed as long as there have been comedians, the genre reached its zenith in the vaudeville era. The vaudeville team Olsen and Johnson used prop comedy extensively in their long running Broadway revue Hellzapoppin.
A prop comic is a comedian who uses prop comedy. Prop comics are sometimes looked down upon by other comedians, and the term is sometimes used derisively. However, some, such as Tommy Cooper, rose to critical acclaim as their props revolved around a gimmick (such as Cooper's magic) and the comedian's character around that gimmick.