Definition
An ATC instruction used to require an aircraft to fly directly over a specified fix, typically as part of a clearance phrase such as 'cross (fix) at (altitude)' or 'cross (fix) at or above/below (altitude).' It directs the pilot to overfly the named point and, when included, to be at the specified altitude as the aircraft passes that point.
Plain English
ATC is telling you to fly directly over a specific named point on your route, and if they give an altitude, to be at that altitude when you pass over it.
Context Anchor
Used in air traffic control clearances, instrument flying, and arrival or departure instructions when a controller needs the aircraft at a certain point, often at a certain altitude.
Derivation
Cross' here keeps its everyday sense of passing over or through a point. In ATC use it has been narrowed to mean 'pass directly over this named fix,' often paired with an altitude requirement.
Why Pilots Care
Ensures compliance with terrain clearance, traffic separation, and published procedure constraints.
Intuition Check
Do not read cross as just turning across something or crossing a line on a map. In this use, it means reach or pass a named navigation point, usually while meeting any stated altitude requirement.
Example Sentence 1
ATC instructed the pilot to cross LINDEN at or above 8,000 feet.
Example Sentence 2
We crossed the fix on schedule and began the descent segment of the arrival.