This is what it has to say about 'nerd':
Nerd, as a stereotypical or archetypal designation, refers to people of above-average intelligence whose interests (often in science and mathematics) are not shared by mainstream society.
... beginning in the late 1990s, many nerds on the Internet reclaimed the word nerd as a badge of pride and began using it as a positive description of a technically-competent person. Although traditionally used to describe men and boys, the terms "nerd" and "geek" have been adopted by many women interested in technology, science, mathematics and other typically male-dominated intellectual fields as badges of their accomplishments in these areas.
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