A person who speaks colloquially or uses informal, conversational language; someone who studies or uses colloquial speech.
From Latin 'colloquium' (conversation, conference) combined with '-ist' (a person who practices or studies something), referring to one who uses or specializes in informal speech.
A colloquialist is basically someone who gets paid to study how real people actually talk—not the fancy Shakespeare way, but how your friends actually chat, with 'gonna' and 'you know' included!
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