A person (or style of action) characterized by aggressive, violent, or reckless behavior with excessive force; from the action movie character.
From the character John Rambo in the 1982 film 'First Blood.' The character's name origin is unclear, but it became genericized to describe anyone operating with brutal, unstoppable force.
It's fascinating that a fictional character's name became a dictionary word so quickly—'Rambo' entered English as slang in the 1980s, a rare example of a proper noun becoming a common adjective within a single decade due to pop culture impact.
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