A woman who creates, originates, or founds something: "the discovery of radium, which made Marie Curie mother to the Atomic Age\u201d ( Alden Whitman). A female person who is pregnant with or gives birth to a child. A female person whose egg unites with a sperm, resulting in the conception of a child. A woman who adopts a child. A woman who raises a child. A female parent of an animal. A female ancestor. A woman who holds a position of authority or responsibility similar to that of a mother: a den mother. Roman Catholic Church A mother superior. Roman Catholic Church Used as a form of address for such a woman. A creative source; an origin: Philosophy is the mother of the sciences. Used as a title for a woman respected for her wisdom and age. Maternal love and tenderness: brought out the mother in her. The biggest or most significant example of its kind: the mother of all battles. Vulgar Slang Something considered extraordinary, as in disagreeableness, size, or intensity. Relating to or being mother. Characteristic of a mother: mother love. Being the source or origin: the mother church. Derived from or as if from one's mother; native: one's mother language. To give birth to; create and produce. To watch over, nourish, and protect maternally. To act or serve as a mother. A stringy slime composed of yeast cells and bacteria that forms on the surface of fermenting liquids and is added to wine or cider to start the production of vinegar.