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1. A geological formation consisting of an underground enclosure with access from the surface of the ground or from the sea

1. Hollow out as if making a cave or opening
   "The river was caving the banks";
   - undermine
    
2. Explore natural caves
   - spelunk [N. Amer], pothole [Brit]

Derived forms: caved, caving, caves

Type of: core out, explore, formation, geological formation, hollow, hollow out

Encyclopedia: Cave, Stephen