陽よう子し線せんMeanings1nounproton beamTechnical term used in physics, medicine (e.g., proton therapy), and related fields.陽よう子し線せん治ち療りょうは、がんの放ほう射しゃ線せん治ち療りょうの一いっ種しゅです。Proton beam therapy is a type of radiation therapy for cancer.