It's a noun with several meanings:
* A source of inspiration, especially in artistic creation. (e.g. "The artist found his muse in nature.")
* A person or thing that is the object of someone's admiration or love. (e.g. "He dedicated his book to his muse.")
* A deity or spirit that inspires creative activity. (e.g. "The Muses were the goddesses of the arts in Greek mythology.")
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