Definition
An ATC instruction directing a pilot to fly a specified racetrack-shaped pattern at a designated fix while waiting for further clearance. A complete holding clearance includes the holding fix, the radial, course, bearing, airway, or route on which the aircraft is to hold, the leg length if other than standard, the direction of turn if non-standard (standard is right turns), and an expect-further-clearance (EFC) time.
Plain English
Instructions from ATC telling you to fly a specific looping pattern over a chosen point in space and wait there until they tell you what to do next.
Context Anchor
Used in instrument flying when ATC needs to delay an aircraft, sequence traffic, protect airspace, or keep an aircraft at a safe location before the next clearance.
Derivation
"Holding" comes from the everyday sense of holding position -- staying put. "Clearance" in ATC means formal permission to do something. Together: formal permission (and instruction) to stay in one area.
Why Pilots Care
Keeps aircraft safely separated and prevents uncontrolled orbiting while ATC manages arrival flow.
Intuition Check
Do not read holding clearance as a vague instruction to slow down or simply wait. It is a specific ATC clearance to fly a defined holding pattern at a defined place.
Example Sentence 1
Approach issued a holding clearance at the LOM, instructing the pilot to hold northeast on the 045 radial with one-minute legs and to expect further clearance at 1745Z.
Example Sentence 2
After reading back the holding clearance, the pilot climbed to the assigned altitude and entered the published holding pattern.