- 1: an unfilled space : cavity, hole
- 2: a depressed or low part of a surface; especially : a small valley or basin
Hollow is a term meaning a small vee-shaped riverine type of valley with moderately sloped sides pitched more gently than and both broader and larger than a ravine. The term is used primarily within and in the states bordering Appalachia (The Appalachian Mountains, from New England to Mississippi) where some local glaciation has broadened ravines into a wider form. Frequently pronounced "Holler" in the central and southern Appalachia states.