resonant

adj. echoing, reverberating; causing echoes, causing reverberation

This article is about resonance in physics. For other senses of this term, see resonance (disambiguation). In physics, resonance is the tendency of a system to oscillate at maximum amplitude at a certain frequency. This frequency is known as the system's resonance frequency. When damping is small, the resonance frequency is approximately equal to the natural frequency of the system, which is the frequency of free vibrations.
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Adjective
1. inducing resonance; "resonant frequency"
(similar) reverberant, ringing
2. characterized by reverberation; "a resonant voice"; "hear the rolling thunder"
(synonym) resonating, resounding, reverberating, reverberative, rolling
(similar) reverberant, ringing

adj. syntonic, pertaining to resonance

(a.)
Returning, or capable of returning, sound; fitted to resound; resounding; echoing back.