Definition
A circle, graduated in degrees from 000° to 359°, printed on aeronautical charts and aerodrome surfaces to show direction with reference to magnetic north (or, in some cases, true north).
Plain English
A 360-degree direction circle that shows which way is which. It is used on charts to read headings and bearings, and painted on the ground at airports as a reference for checking aircraft compasses.
Context Anchor
Seen on some aviation charts and on airport surfaces used for checking an aircraft compass.
Derivation
From the old practice on mariners' charts of drawing a decorative circle marked with the cardinal directions; the points radiating outward looked like the petals of a rose. Aviation inherited the same idea and the same name.
Why Pilots Care
Lets pilots read magnetic headings and bearings straight from the chart during flight planning without extra calculations.
Intuition Check
A compass rose is not the compass instrument in the cockpit. It is the marked circle used as a direction reference on a chart or on the ground.
Example Sentence 1
He centered the VOR needle and read his radial directly off the compass rose printed around the station.
Example Sentence 2
While reviewing the sectional, she used the compass rose printed near the VOR to confirm the inbound radial.