Loosely defined, a Schwarzschild radius is a point where a sphere is forced to become a black hole. The term Schwarschild is a portmanteau of two German words: Schwarz, meaning "black", and schild, meaning "shield", which makes sense. Schwarz, through Middle German swarz, Old High German swarz, and Proto-Germanic swartaz, comes from the Proto-Indo-European root swordo, meaning "black". Very little semantic change for that term. Schild, through Middle German schilt and Old High German scilt, comes from the Proto-Germanic word skelduz, which also meant "shield" and is the etymon of the English word shield, by way of the Old English word scild. Skelduz is from Proto-Indo-European skel, which meant "to cut", under the connection that you cut wood to make a shield. So, now we know how Schwarzschild came to mean "black shield". HOWEVER, that was all just the last name of Karl Schwarzschild, a German physicist who first theorized the radius. This may be the single most incredible coincidence in all of scientific etymology and is amazing
Adam Aleksic, a freshman studying linguistics at Harvard University, has been described as the internet's sixth most famous etymologist. He has disturbing interests in words, vexillology, geography, board games, limericks, and law, and he loves writing about himself in the third person.
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