A mother is the natural or social female parent of an offspring.

In the case of a mammal such as a human, the mother gestates her child, which is called first an embryo, and then a fetus.^[1] This gestation occurs in the womb from conception until the fetus is sufficiently developed to be born. The mother then goes into labor and gives birth. Once the child is born, the mother produces milk, a process called lactation, to feed the child.

Mothers typically fulfill the primary role in the raising of children. The title mother is often given to a woman other than biological parent, if it is she who fulfills this role. This is most commonly either an adoptive mother or a stepmother (the biologically unrelated wife of a child's father). Currently, with advances in reproductive technologies, the function of biological motherhood can be split between the genetic mother (who provides the ovum) and the gestational mother (who carries the pregnancy), and in theory neither might be the social mother (the one who brings up the child).

The term mother can also refer to a person with stereotypical traits of a mother such as nurturing and other-centeredness.

Familiar or colloquial terms for mother in English are:

• mum or mummy, usual in the UK, Australia, New Zealand, and parts of Canada;
• mom or mommy, in North America (especially the U.S.), and in the Midland areas of England; especially Birmingham and the Black Country. Mommy is considered baby talk. Most adults in these regions switch to the term mom as they approach the teen years.
• mam or mammy, North Wales, the South Wales valleys, Ireland, Northern England and The Netherlands;
• mama and ma, in parts of the middle east, Latin America and other Spanish-speaking cultures. Mama is often used in rural areas of the midwest and south eastern regions of the US. Ma is a common term in various parts of the US including the north east.

In many other languages, similar pronunciations apply; maman in French, or mamma in Italian, or mamãe in Portuguese. Mama, borrowed from the English, is in common use in Japan. In many south Asian cultures, and the middle east the mother is known as amma or oma or ammi or "ummi", or variations thereof. The "M" sound seems to be near universal to the word mother in many different languages; this is thought to be related to one of the first sounds an infant learns to control, the smacking of its lips together as it comes off the breast. (See breastfeeding.) Many times these terms denote affection or a maternal role in a child's life.