1. The bed of a stream of water; the groove through which a stream flows (digging a deeper channel was thought to help protect the river from flooding).
main channel. The bed over which the principal volume of water flows; the deepest and most navigable part of a channel.
natural channel. The naturally formed bed and banks of a stream.
natural flood channel. A channel through which floodwaters naturally accumulate and flow downstream.
2. The line of deep water that shipping vessels follow (a shipping channel).
3. A water route between two islands or an island and a continent (the English Channel).
4. A mode of transmitting something (the news channel).
