Female romantic partners; or female friends, sometimes with romantic or sexual implications.
'Girl' from Old Norse/Germanic roots, plus 'friend' from Old English 'freond' (one who loves). The compound emerged in the 18th century with romantic meaning.
The word 'girlfriend' is remarkably recent—before the 1800s, romantic partners were 'sweethearts,' 'paramours,' or 'lovers,' which means modern dating culture created new vocabulary to describe a new social reality.
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