Having an empty space or cavity, natural or artificial, within a solid substance; not solid; excavated in the interior; as, a hollow tree; a hollow sphere.
- Having a cavity, gap, or space within: a hollow wall.
- Deeply indented or concave; sunken: "His bearded face already has a set, hollow look” ( Conor Cruise O'Brien).
- Without substance or character: a hollow person. See Synonyms at vain.
- Devoid of truth or validity; specious: "Theirs is at best a hollow form of flattery” ( Annalyn Swan).
- Having a reverberating, sepulchral sound: hollow footsteps.
- A cavity, gap, or space: a hollow behind a wall.
- An indented or concave surface or area.
- A void; an emptiness: a hollow in one's life.
- A small valley between mountains.
- To make hollow: hollow out a pumpkin.
- To scoop or form by making concave: hollow out a nest in the sand.
- To become hollow or empty.