Plain English Meaning
The official books, manuals, charts, and notices that tell pilots the rules and how to do things in the air. They are the trusted source pilots and instructors rely on instead of guessing or relying on memory.
Full Definition
Official documents produced by the FAA and other authorities that provide the regulations, procedures, charts, and operational information pilots need to fly safely and legally. Examples include the Federal Aviation Regulations (14 CFR), the Aeronautical Information Manual (AIM), Advisory Circulars, FAA handbooks (such as the Pilot's Handbook of Aeronautical Knowledge and the Airplane Flying Handbook), , the , and Notices to Air Missions ().