Definition of: hollow

(hol′ō) adjective
1. Having a cavity or depression scooped out; not solid: a hollow tree.
2. Sunken; fallen: hollow cheeks.
3. Empty; vacant; hence, worthless; fruitless; insincere.
4. Sounding like the reverberation from an empty vessel or cavity; deep; murmuring.
—noun
1. Any depression in a body; a cavity.
2. A valley.
3. A concave tool for making grooves and moldings. See synonyms under HOLE.
—v.t. & v.i. To make or become hollow: usually with out.
—adverb Colloq. Completely; thoroughly.
—to beat all hollow To surpass completely. [OE holh]
—hol′·low·ly adverb
—hol′low·ness noun