Morgan's roots are genuinely contested, with proposed Welsh meanings including "sea-born" and "bright circle," and further complexity added by its long association with a shape-shifting enchantress in Arthurian legend. Across the competing readings runs a thread of something elemental and hard to pin down -- fluid rather than fixed.
When a king or prince sets forth to journey, be sure reject that time when Cancer ascends. - William Lilly (1602.-1681.)