Colt \c(o)-lt\ as a boy's name is pronounced kolt. It is of Old English origin, and the meaning of Colt is "young horse; frisky". Occupational name. Variants are English surnames used as given names. The Colt revolving-breech pistol, or revolver, is the invention of 19th-century inventor Samuel Colt.
For more information, see also the related name Colbert.