channel noun definition in Rivers and lakes topic from the Oxford Advanced Learner's Dictionary

channel

 noun: Rivers and lakes topic
1 [countable] a passage that water can flow along, especially in the ground, on the bottom of a river, etc. drainage channels in the rice fields2 [countable] a deep passage of water in a river or near the coast that can be used as route for ships3 [countable] a passage of water that connects two areas of water, especially two seas the Bristol Channel