One possibility is that it comes from a Celtic place name, such as Deva or Debana, ultimately deriving from the Latin divius ("divine").

However, the course of the Debantbach stream on the alluvial fan in the Isel Valley, at the time of Aguntum, could not be accurately reconstructed.

The Debantbach is a stream originating in the Hohe Tauern National Park at an elevation of 2540 meters west of the Hochschober and below the southern Leibnitzörl in the municipality of Nußdorf-Debant.

It flows in a westerly direction through a varied landscape with changing geography before uniting with the Gößnitzbach and other smaller streams at the head of the Debant valley.

After passing the Roracher Alm, the Debantbach reaches the border between the municipalities of Nußdorf-Debant and Iselsberg-Stronach, which it follows until it leaves the Debant valley through the Debant Gorge and reaches the Drava in a wide alluvial cone near the district of Kapaun.