verb, -nat⋅ed, -nat⋅ing.| 1. | to resound. |
| 2. | to act as a resonator; exhibit resonance. |
| 3. | Electronics. to reinforce oscillations because the natural frequency of the device is the same as the frequency of the source. |
| 4. | to amplify vocal sound by the sympathetic vibration of air in certain cavities and bony structures. |
| 5. | to cause to resound. |