Definitions
1.NounAn aunt on one's mother's side of the family, including both
A sister of one's mother.
A sister-in-law of one's mother; the wife or ex-wife of a maternal uncle.
2.NounA sister of one's mother.
3.NounA sister-in-law of one's mother; the wife or ex-wife of a maternal uncle.
4.NounA similar great aunt, etc.