1. the quality or state of being empty inside; the condition of having a hole or cavity within
2. lack of substance, sincerity, or genuine meaning; superficiality
3. a dull or muffled quality of sound

Examples

• The hollowness of the tree trunk made it easy to carve.
• Critics attacked the speech for its hollowness and lack of real solutions.
• She felt a deep hollowness in her chest after hearing the sad news.
• The hollowness of his promises became apparent over time.
• The drum's hollowness gave it a rich, resonant tone.
• There was a hollowness to his laughter that suggested he wasn't truly happy.