U

girl

noun

a female child, from birth to full growth.
a young, immature woman, especially formerly, an unmarried one.
a daughter: My wife and I have two girls.
Informal: Sometimes Offensive. a grown woman, especially when referred to familiarly: She’s having the girls over for bridge next week.
a girlfriend; sweetheart.
Older Use: Usually Offensive. a female servant, as a maid.
Older Use: Usually Offensive. a female employee, especially an office assistant.
a female who is from or native to a given place: She’s a Missouri girl.
girls, (used with a singular or plural verb)
1. a range of sizes from 7 to 14, for garments made for girls.
2. a garment in this size range.
3. the department or section of a store where these garments are sold.
girls, Slang. one’s breasts (usually preceded by the, my, etc., and primarily used self-referentially by women).

noun

a female child from birth to young womanhood
a young unmarried woman; lass; maid
informal a sweetheart or girlfriend
informal a woman of any age
an informal word for daughter
a female employee, esp a female servant
Southern African derogatory a Black female servant of any age
the girls (usually plural) informal a group of women, esp acquaintances

c.1300, gyrle “child” (of either sex), of unknown origin; current scholarship [OED says] leans toward an unrecorded Old English *gyrele, from Proto-Germanic *gurwilon-, diminutive of *gurwjoz (apparently also represented by Low German gære “boy, girl,” Norwegian dialectal gorre, Swedish dialectal gurre “small child,” though the exact relationship, if any, between all these is obscure), from PIE *ghwrgh-, also found in Greek parthenos “virgin.” But this is highly conjectural. And Liberman (2008) writes:

Girl does not go back to any Old English or Old Germanic form. It is part of a large group of Germanic words whose root begins with a g or k and ends in r. The final consonant in girl is a diminutive suffix. The g-r words denote young animals, children, and all kinds of creatures considered immature, worthless, or past their prime.

Another candidate is Old English gierela “garment” (for possible sense evolution in this theory, cf. brat). Like boy, lass, lad it is of obscure origin. “Probably most of them arose as jocular transferred uses of words that had originally different meaning” [OED]. Specific meaning of “female child” is late 14c. Applied to “any young unmarried woman” since mid-15c. Meaning “sweetheart” is from 1640s. Girl next door as a type of unflashy attractiveness is recorded by 1953.

Doris [Day] was a big vocalist even before she hit the movies in 1948. There, as the latest movie colony “girl next door,” sunny-faced Doris soon became a leading movie attraction as well as the world’s top female recording star. “She’s the girl next door, all right,” said one Hollywood admirer. “Next door to the bank.” [“Life” magazine, Dec. 22, 1958]

Girl Friday is from 1940, a reference to “Robinson Crusoe.”