Morgan \m(o)-rgan, mor-gan\ as a girl's name (also used as boy's name Morgan), is pronounced MOR-gen. It is of Welsh and Old English origin, and the meaning of Morgan is "circling sea or great brightness; bright or white sea dweller". The given meanings suggest the magical machinations of King Arthur's jealous sister, Morgan le Fay. Usage for girls increased during the 1980s, probably due to actress Morgan Fairchild. Morgaine and Morgayne are medieval Irish forms.