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The word “muscle” was first used by Middle French speakers in the 14th century. But the word evolved from the existing Latin words “mus” meaning “mouse” and “musculus,” which translates to both “little mouse” and “muscle.”
Yes – ancient Romans believed that certain muscles, especially bicep muscles, looked like little mice running under a person’s skin. If you want to flex right now to see what they were talking about, we don’t blame you.
After “muscle” was adopted by the French, it later showed up in Late Middle English and is still used in modern English today.
Although “muscle” developed from a Latin root, the Romans weren’t the only ones who associated muscles with mice. Take the prefix “myo-”. This term is used to refer to muscles in medical terminology today, like in the word for muscle cell (myocyte). “Myo” stems from the Greek word “mŷs” which translates to both muscle and mouse.
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