1. a female parent.
2. (often initial capital letter) one's female parent.
3. a mother-in-law, stepmother, or adoptive mother.
4. a term of address for a female parent or a woman having or regarded as having the status, function, or authority of a female parent.
5. term of familiar address for an old or elderly woman.
6. mother superior
7. a woman exercising control, influence, or authority like that of a mother: to be a mother to someone.
8. the qualities characteristic of a mother, as maternal affection: It is the mother in her showing itself.
9. something or someone that gives rise to or exercises protecting care over something else; origin or source.
10. (in disc recording) a mold from which stampers are made.

11. being a mother: a mother bird.
12. of, pertaining to, or characteristic of a mother: mother love.
13. derived from or as if from one's mother; native: his mother culture.
14. bearing a relation like that of a mother, as in being the origin, source, or protector: the mother company and its affiliates; the mother computer and its network of terminals.