drain·pipe
noun/ˈdreɪnpaɪp/
/ˈdreɪnpaɪp/
enlarge image(North American English also downspout)a pipe that carries rainwater from the roof of a building to a drain（把雨水从屋顶输送到下水道的）雨水管，排水管 - a pipe that carries dirty water or other liquid waste away from a building
（排放建筑物内污水的）排水管，泄水管