Colby is a unisex name that originated from the Old English word "col," meaning "dark" or "coal." It is often used as both a first and last name, giving it a strong and versatile quality. People with the name Colby are often described as intelligent, charismatic, and creative individuals. The name has become increasingly popular in recent years, especially in the United States. Famous individuals with the name Colby include actor Colby Donaldson and musician Colby O'Donis.