Mercia \m(e)-rcia, mer-cia\ as a girl's name is of Old English origin. Place name: the English kingdom of Mercia comprised much of England from the sixth to the ninth century. See also Mercy.

Baby names that sound like Mercia are Marcia, Mercie and Merci. Other similar baby names are Tercia, Mera, Cericia, Darcia, Marcie, Martia, Marsia, Marci, Maria, Meris, Maricia, Markia, Marnia, Moria, Melicia, Mercey, Merial, Merola, Merla, Merona, Merril, Merrie, Merri, Meriam, Moraia, Merna, Myrtia, Persia, Tersia and Tertia.