Definition
An ATC clearance authorizing a pilot to execute any standard or special instrument approach procedure published for that airport. When a specific approach is named (for example, 'cleared ILS Runway 27 approach'), the pilot must fly that procedure; when only 'cleared for the approach' is issued, the pilot may select any published instrument approach for the airport.
Plain English
Permission from air traffic control to begin flying an instrument approach to land. If the controller names a specific approach, fly that one. If they don't, you may choose any published approach for that airport.
Context Anchor
Heard during instrument arrivals, usually after vectors, routing, or descent planning as the aircraft is being set up to join the final part of the approach.
Derivation
Clear comes from the idea of being free from obstruction or allowed to proceed. In aviation, cleared means official permission from air traffic control, not just that the path looks open. Approach means the planned movement toward the airport or runway before landing.
Why Pilots Care
It authorizes descent and course changes per the approach procedure without waiting for further instructions until landing or a missed approach.
Intuition Check
Do not read cleared as meaning everything is automatically allowed. Here, it means ATC has authorized the approach procedure; it does not cancel restrictions, and it is not the same as cleared to land.
Example Sentence 1
After the controller said 'cleared for the ILS Runway 9 approach,' the pilot intercepted the localizer and began the descent on the glideslope.
Example Sentence 2
The controller cleared the flight for the approach so the crew could configure for landing.