A person who studies or theorizes about the origin and formation of the universe.
From cosmogony + -er (agent suffix). This occupational noun follows the standard English pattern of adding -er to create 'one who does' or 'one who studies,' similar to philosopher or geographer.
Cosmogoners were especially important during the Scientific Revolution when people like Kant and Laplace completely reimagined how planets and stars could form without divine intervention. Today we'd call them cosmologists, but the older term reminds us this work combines science with ancient philosophical questions.
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