Mab \mab\ as a girl's name is of Irish, Gaelic and Welsh origin, and the meaning of Mab is "joy, hilarity; baby". In old English, Welsh, and Irish stories, Queen Mab is monarch of the fairies.

Mab has 3 variant forms: Mave, Mavis and Meave.

For more information, see also related names Amabel and Mabel.