noun
cable layer; cable-laying ship
A vessel designed to lay submarine communication or power cables on the seabed.
海底電線敷設船が太平洋横断ケーブルを敷設した。
A cable layer laid a trans-Pacific cable.
敷設船 is a general term for a laying ship (e.g., cable or pipeline), while 海底電線敷設船 specifically refers to a submarine cable-laying vessel.
Compound of 海底 (seabed) + 電線 (electric wire/cable) + 敷設 (laying) + 船 (ship).