- MalcolmA male given name from Scottish Gaelic or Goidelic, variant of Calum and Callum, feminine equivalent Malcolmina, equivalent to Scottish Gaelic Maol Chaluim.
- colombophiliaPigeon fancying.
- columbiadA form of cannon from the 19th century, mostly used for seacoast protection. It is a large-caliber, smoothbore, muzzle-loading cannon designed for launching shot or shells with heavy charges of powder, at both high and low angles of elevation.