Definition
The Code of Federal Regulations is the official, codified collection of rules issued by U.S. federal agencies. For aviation, the rules issued by the Federal Aviation Administration are found in Title 14 of the CFR, which covers areas such as airman certification, aircraft operations, airworthiness standards, and air traffic procedures.
Plain English
CFR is the official rulebook of the U.S. government, organized by topic. The aviation rules pilots must follow live in Title 14 of that rulebook.
Context Anchor
Seen in FAA publications, training materials, checkride preparation, and rule citations that point to a specific federal aviation requirement.
Derivation
Code here means an organized, official collection of laws — the same sense as 'building code.' Federal Regulations are rules made by federal agencies (like the FAA) under authority given to them by Congress. So CFR is simply the organized rulebook of those agency rules.
Why Pilots Care
Pilots must know and comply with the applicable CFR sections that apply to their certificate and operations; failure to follow them can result in certificate action or penalties.
Intuition Check
Do not think of CFR as a separate aviation handbook. It is the larger federal rule collection; aviation rules are one part of it.
Example Sentence 1
The pilot reviewed 14 CFR Part 91 before the flight to confirm the required preflight actions.
Example Sentence 2
During the oral exam the examiner asked how 14 CFR Part 61 applies to recent flight experience requirements.