What is Secure Channel?

Legal Definition
In cryptography, a secure channel is a way of transferring data that is resistant to overhearing and tampering. A confidential channel is a way of transferring data that is resistant to overhearing (i.e., reading the content), but not necessarily resistant to tampering. An authentic channel is a way of transferring data that is resistant to tampering but not necessarily resistant to overhearing.
-- Wikipedia
Legal Definition
A path of communication that is protected by interference from a third party.