Definition
The direction the airplane's nose is pointing relative to magnetic north, as shown on the magnetic compass or heading indicator in the cockpit.
Plain English
The number on the compass or heading instrument that tells the pilot which way the nose of the airplane is pointing, measured from magnetic north.
Context Anchor
Seen during straight flight when the pilot checks whether the airplane is staying pointed in the selected direction.
Derivation
Magnetic' refers to magnetic north (the direction a compass needle points), not true north. 'Heading' is the direction the nose is pointing. 'Indication' simply means the reading shown on the instrument. Together: what the instrument shows for the airplane's nose direction relative to magnetic north.
Why Pilots Care
Allows the pilot to hold a steady direction using the Earth's magnetic field when visual references are limited or unavailable.
Intuition Check
Do not read “heading” as the path the airplane is actually making over the ground. Here it means where the nose is pointed, measured from magnetic north. Also, “indication” means the instrument reading; it may need normal pilot judgment to interpret correctly.
Example Sentence 1
After rolling out of the turn, the pilot checked the magnetic heading indication and confirmed it read 270 as assigned.
Example Sentence 2
With the magnetic heading indication steady on 270, the airplane was pointed due west.