A container with an open hole or neck containing a column of compressible fluid (gas) and frequently used to attenuate a certain frequency, as to eliminate noise.

(chemistry) the mesomeric effect

(chemistry) A compound for which no simple structure can be written, but which actually has a structure midway between two simple ones - normally one polar and one nonpolar.

A chamber whose dimensions allow sound to echo and build up. / A similar chamber that allows resonance of electromagnetic waves.

A chamber in a musical instrument for increasing its sonority.

plural of resonance box

The peculiar high-pitched quality of sound produced by percussion over the intestines, etc. when they contain air.

plural of Schumann resonance

Any of a set of spectrum peaks in the extremely low-frequency (ELF) portion of the Earth's electromagnetic field spectrum, generated and excited by lightning discharges in the cavity formed by the Earth's surface and the ionosphere.

A form of waveguide, closed at each end, used to create an intense electromagnetic wave