A scholar or anthropologist who believes that cultural traits and innovations spread from specific centers through contact and exchange.
From diffusion + -ist (suffix for believers in a doctrine or practitioners). The -ist suffix creates agent nouns for people who follow particular theories or perform particular roles.
Early diffusionists tried to trace all human cultures back to a few origin points, leading to some spectacularly wrong conclusions—the theory shows how even smart people can over-apply a good idea.
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