We got the beat
Though the musical sense of the word beat didn’t appear until the 1840s, beat first showed up in Old English as a verb meaning to thrash or inflict blows on. It came from the Proto-Indo-European word meaning to strike or thrust. Linguists represent this word as *bhau-.
*Bhau- is the source of a heap of modern English words. Here are a few:
The verb butt appeared in English in about 1200, meaning to strike with the head.
*Bhau- also gave us the noun bat, meaning a stick or club (obviously used to beat something). Bat has been with us since Old English. For the purpose of making sense of the next few etymologies, it’s important to note that the part of the bat one grips is typically narrow, while the business end of a bat is comparably thick.
When butt first transitioned to a noun in English (1200-1300) it meant both thick end and flat fish (possibly - but not definitively - due to the need to tenderize the fish by beating it with a bat). We still see the meaning flatfish in the word halibut which appeared in the 1400s.The meaning human posterior (another thick end) also showed up in the 1400s, and by the 1600s the noun butt also meant the target of a joke. By the mid-1800s butt also meant the remaining end of a smoked cigarette. Both butt in & buttinski showed up about 1900.
The word buttress (an element of a building that thrusts out from the primary structure) appeared in English in the 1300s.
Since the 1300s we’ve been thrusting buttons through button-holes.
And in argumentation, both the words rebut (1300s) & refute (1500s) mean to strike back & were born of the word *bhau-.
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