Definition
A directive from ATC meaning the controller or pilot must pause briefly because attention is required elsewhere. It is not an approval, denial, or clearance. The person who said 'stand by' will return to the transmission as soon as possible. If the delay becomes lengthy, the caller should re-establish contact. 'Stand by' is not used as a means of acknowledgment or compliance.
Plain English
Wait a moment — I'm busy with something else and will get back to you shortly. It does not mean yes, no, or approved.
Context Anchor
Heard on aviation radios when a controller or pilot needs a pause before answering or continuing the exchange.
Derivation
Stand by comes from the older idea of standing nearby, ready to act when called. In radio use, it means stay ready and wait for the next communication.
Why Pilots Care
Prevents simultaneous transmissions and allows the controller or pilot time to gather necessary information without rushing.
Intuition Check
Do not treat “stand by” as permission. It only means “wait; I will get back to you.”
Example Sentence 1
After the pilot requested a deviation for weather, the controller replied, 'Stand by,' and the pilot maintained the current heading until further instruction.