Definition
Used by ATC or pilots when a control instruction or response must be acted upon without delay because a hazard or compromise to safety exists. It signals that the action takes priority over routine sequencing or convenience.
Plain English
Do it right now, not in a moment. Something about the situation is unsafe or about to become unsafe, so the instruction can't wait.
Context Anchor
You will hear this in radio communication between pilots and air traffic control when quick action is needed for safety.
Derivation
Immediately comes from Latin roots meaning “with nothing in the middle.” That fits the aviation meaning: no waiting, no extra step, and no unnecessary delay before acting.
Why Pilots Care
Instant compliance prevents loss of separation or collision.
Intuition Check
Do not read “immediately” as “rush and stop thinking.” It means act without delay, while still flying the aircraft safely.
Example Sentence 1
"Cessna Three Four Lima, turn left heading two-seven-zero immediately, traffic at your two o'clock."
Example Sentence 2
The controller said descend immediately during the emergency.