Here are some examples of how it can be used as a noun:
* Physical Channel: "The Panama Canal is a vital shipping route."
* Communication Channel: "We're going to communicate through the official channels."
* TV Channel: "My favorite TV channel is the Discovery Channel."
* Sales Channel: "They're expanding their sales channels to reach new customers."
Let me know if you'd like more examples or want to know more about the different ways "channel" can be used!