Jack \j(a)-ck\ as a boy's name is pronounced jak. It is of Old English origin. Name based on John (Hebrew) "God is gracious", or Jacques, the French form of Jacob (Hebrew) "he who supplants". The name has a rugged, down-to-earth aura. Jackie is used more for girls than for boys. Actors Jackie Gleason, Jack Nicholson, Jack Black; comedian Jack Benny; exercise guru Jack LaLanne.
For more information, see also the related name Jackson.