Origin: Old Norse, Sumerian
Meaning: the name of a Norse goddess possibly meaning "daring, brave" or "mother". In Norse mythology, Nanna was a goddess, the wife of Balder, who died of gried when her husband was killed.
Nanna is also the name of a Sumerian god of the moon (also known as Sin in Akkadian mythology). The meaning behind the name is unclear though it could be related to "moon".
Nanna is also a term for grandmother.
Nanna could also be a variant spelling of Nana, which has multiple meanings: a Japanese feminine name meaning either "seven" or "vegetables, greens"; a Greek diminutive of Ioanna, the feminine form of John meaning "Yahweh is gracious"; or a Georgian feminine name of unknown meaning.