私鉄
してつ · shitetsu · JLPT N2 · noun
railway
🚃 私 (private) + 鉄 (railway): a privately owned train line, as opposed to JR or city subway
私 means 'private' and 鉄 is short for 鉄道, 'railway'. Kanji 鉄 also means 'iron', but here it stands for the tracks. Many Japanese cities have both 公営 (public) and 私鉄 lines.