- A mountain slope which receives little sunshine, especially one facing north. Compare with adret.Más ejemplos en oraciones
- This kind of moor, well represented in Tarentaise is characterised by ubacs (north or north west facing slopes).
- Adrets (south-facing slopes) are most suitable for building villages and growing crops, whilst ubacs (north-facing slopes) often remain wooded.
- Ubacs are colder, have more snow cover and a longer duration of snow cover.
1930s: from French, apparently from Latin opacus 'shady'.