ミュオンalso: ミューオンMeanings1nounmuonphysicsAn elementary particle similar to an electron but with a greater mass. Used in physics contexts.ミュオンは宇う宙ちゅう線せんに含ふくまれている。Muons are contained in cosmic rays.ミュオンの寿じゅ命みょうは約やく2.2マイクロ秒びょうだ。The lifetime of a muon is about 2.2 microseconds.