The term 'dweeb' is usually negative, suggesting that someone is socially awkward or uncool. Although he's really smart, some people unfairly call him a dweeb.
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Informal Use
'Dweeb' is informal and may be considered rude or insulting if used in polite company. I apologize for calling him a dweeb at the dinner table, it was inappropriate.
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Jocular Mockery
Sometimes used jokingly among friends without intention to harm. My friends laughed when I tripped, calling me a clumsy dweeb.