noun
baseball-obsessed boy; boy who lives for baseball
Refers to a boy, typically elementary or middle school age, who is extremely passionate about baseball, often spending most of his free time playing or practicing.
彼は典型的な野球少年で、放課後はいつもグラウンドにいる。
He's a typical baseball-obsessed boy; after school he's always on the field.
うちの息子は野球少年で、休みの日も朝から晩まで練習している。
My son lives for baseball; even on days off he practices from morning till night.
Compound of 野球 (baseball) and 少年 (boy).