Plain English Meaning
The CFRs are the official written rulebook of the U.S. federal government. Aviation has its own section of that rulebook (Title 14), and that is where the rules pilots have to follow live.
Full Definition
The Code of Federal Regulations is the official compilation of the permanent rules issued by the executive departments and agencies of the U.S. federal government. It is organized into 50 numbered titles by subject area. Aviation rules are contained in Title 14, which covers aeronautics and space, and includes the parts that govern pilot certification, aircraft operation, airworthiness, and air traffic procedures.
Context Anchor
Seen in FAA handbooks when a topic has legal requirements in addition to flying technique, such as equipment, training, or for .