noun
railway ferry; train ferry
A ferry service that carries railway cars or connects two railway networks, often across a strait or body of water.
青函トンネルが開通する前は、本州と北海道の間を鉄道連絡船が結んでいた。
Before the Seikan Tunnel opened, railway ferries connected Honshu and Hokkaido.
Compound of 鉄道 (railway) + 連絡 (connection) + 船 (ship).