verb

cause the water or other liquid in (something) to run out, leaving it empty or dry.

we drained the swimming pool

empty (out),remove the contents of,void,clear (out),unload,evacuate

noun

a channel or pipe carrying off surplus liquid, especially rainwater or liquid waste.

sewer,channel,conduit,ditch,culvert,duct,pipe,tube,gutter,groove,furrow,trough,trench,cut,sluice,spillway,race,flume,chute