resonance

ot noun

1. A short-lived subatomic particle or state of atomic excitation that results from the collision of atomic particles. 2004, When experiments with the first ‘atom-smashers’ took place in the 1950s to 1960s, many short-lived heavier siblings of the proton and neutron, known as ‘resonances’, were discovered. — Frank Close, Particle Physics: A Very Short Introduction (Oxford 2004, p. 35)
2. The quality of being resonant.
3. A resonant sound, echo, or reverberation, such as that produced by blowing over the top of a bottle.
4. The sound produced by a hollow body part such as the chest cavity upon auscultation, especially that produced while the patient is speaking.