Plain English Meaning
A point in the sky identified by saying 'this many degrees out from the station, this many miles away.' Two numbers — a direction and a distance — pin down exactly where the fix is.
Full Definition
Navigation fixes defined by a specific radial (bearing in degrees) and a specific distance (in nautical miles) from a VOR/DME or VORTAC station. The fix is located where that bearing and distance intersect, giving a single, precise point in space.
Context Anchor
Seen on IFR charts, airway descriptions, and instrument route information when a point is identified by a radial or bearing plus a mileage value.
Derivation
The name describes how the fix is built: 'degree' refers to the radial ( bearing from the station), and 'distance' refers to the mileage from that same station. Together they form the fix.