Definition
A small display on the VOR indicator that shows which radial (course) the pilot has selected for navigation. The selected course is set using the Omni Bearing Selector (OBS) knob, and the chosen value appears as a number in the course window at the top of the instrument.
Plain English
It's the little number readout on the VOR instrument that tells you which course you've dialed in to fly to or from the station.
Context Anchor
Seen on VOR indicators when setting or checking the desired course during instrument navigation.
Derivation
Course comes from an older word meaning a path or direction of travel. Window normally means an opening, but on an instrument it means a small display area where information is shown.
Why Pilots Care
It lets the pilot confirm the exact course dialed in so navigation remains accurate and aligned with the intended route or approach.
Intuition Check
Do not read course window as an outside aircraft window. It is a display on the instrument. Also, the course shown is the selected VOR course, not necessarily the airplane’s current heading.
Example Sentence 1
After tuning the VOR, the pilot turned the OBS knob until 270 appeared in the course window.
Example Sentence 2
During the approach briefing the instructor pointed to the course window to verify the inbound radial matched the plate.