girl

n. young female child; young female; woman (Slang); housemaid (Slang)

A girl is a female child, as opposed to a boy, a male child. The age at which a female person transitions from girl to woman varies in different societies; typically the transition from adolescence to maturity is taken to occur in the late teens. The English word (first documented in 1290) originally designated a child of either gender. To designate between the two genders, a female child was called a gay girl, while a male child was called a knave girl. During the 14th century its sense was narrowed to specifically female children. Subsequently, it was extended to refer also to mature but unmarried young women since the 1530s. Usage in the sense of (romantic) "sweetheart" arose in the 17th century.
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n. show girl

n. showgirl (slang)

(n.)
A young person of either sex; a child.
  

(n.)
A roebuck two years old.
  

(n.)
A female servant; a maidservant.
  

(n.)
A female child, from birth to the age of puberty; a young maiden.