A woman is a female human being. The word woman is usually reserved for an adult, with girl being the usual term for a female child or adolescent. The plural women is also sometimes used for female humans, regardless of age, as in phrases such as "women's rights". Women with typical genetic development are usually capable of giving birth from puberty until menopause. There are also trans women (those who have a male sex assignment that does not align with their gender identity), and intersex women (those born with sexual characteristics that do not fit typical notions of male or female).

Etymology
The spelling of "woman" in English has progressed over the past millennium from wīfmann to wīmmann to wumman, and finally, the modern spelling woman. In Old English, wīfmann meant "female human", whereas wēr meant "male human". Mann or monn had a gender-neutral meaning of "human", corresponding to Modern English "person" or "someone"; however, subsequent to the Norman Conquest, man began to be used more in reference to "male human", and by the late 13th century had begun to eclipse usage of the older term wēr. The medial labial consonants f and m in wīfmann coalesced into the modern form "woman", while the initial element wīf, which meant "female", underwent semantic narrowing to the sense of a married woman ("wife").

It is a popular misconception that the term "woman" is etymologically connected to "womb". "Womb" is actually from the Old English word wambe meaning "stomach" (modern German retains the colloquial term "Wampe" from Middle High German for "potbelly").

Terminology
Womanhood is the period in a human female's life after she has passed through childhood and adolescence, generally around age 18.

The word woman can be used generally, to mean any female human,[citation needed] or specifically, to mean an adult female human as contrasted with girl. The word girl originally meant "young person of either sex" in English;[9] it was only around the beginning of the 16th century that it came to mean specifically a female child. The term girl is sometimes used colloquially to refer to a young or unmarried woman; however, during the early 1970s, feminists challenged such use because the use of the word to refer to a fully grown woman may cause offence. In particular, previously common terms such as office girl are no longer widely used. Conversely, in certain cultures which link family honor with female virginity, the word girl (or its equivalent in other languages) is still used to refer to a never-married woman; in this sense it is used in a fashion roughly analogous to the more-or-less obsolete English maid or maiden.

There are various words used to refer to the quality of being a woman. The term "womanhood" merely means the state of being a woman, having passed the menarche; "femininity" is used to refer to a set of typical female qualities associated with a certain attitude to gender roles; "womanliness" is like "femininity", but is usually associated with a different view of gender roles; "femaleness" is a general term, but is often used as shorthand for "human femaleness"; "distaff" is an archaic adjective derived from women's conventional role as a spinner, now used only as a deliberate archaism.

Menarche, the onset of menstruation, occurs on average at age 12–13. Many cultures have rites of passage to symbolize a girl's coming of age, such as confirmation in some branches of Christianity, bat mitzvah in Judaism, or even just the custom of a special celebration for a certain birthday (generally between 12 and 21), like the quinceañera of Latin America.
en.wikipedia.org