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musa f. (Noun) "Muse;" "inspiration"
15th cent. borrowing from Latin Musa 'id.,' from Ancient Greek Μοῦσα ‎(Moûsa). Its origins are hazy. Possibly from Proto-Indo-European *mondh-i̯h2 "the wise one" as an appellation for a Muse. In which case, the name stretches back to an original root *men- "to think" (see mente). But Beekes (2014) notes, the word with its difficult origin may just as well be a loan from a Pre-Greek source.

"The Muses can assist by putting the poet in mind of the relevant material. This is why they are called daughters of Memory, Mnemosyne." M. West, Indo-European Poetry and Myth (2007)