a chemical element. Berkelium is a radioactive metal that is produced artificially from americium and helium. 锫(放射性元素) Word Origin1949: from Berkeley, a city in western California, USA (where it was first made) + -ium.
👨🏻🏫 Mr. Ng 牛津詞典 📚 – oxford.mister5️⃣.net
切換為繁體中文