noun: 1. A hole or recess for a pigeon to nest or rest. 2. One of a series of small compartments for filing papers, etc. 3. A stereotypical category, not reflecting the complexities. verb tr.: 1. To place in, or as if, in a pigeonhole. 2. To lay aside for future consideration. 3. To stereotype, to put into a preconceived, rigid category.