The speed at which a specified acoustic wave (e.g., pressure wave, shear wave, etc.) travels through a material in a specified direction. The wave speed will depend on the material's properties and the dimensions and shape of the object (e.g., the resonator) through which it is traveling. In addition, if the material is orthotropic or anisotropic then the wave speed will depend on the direction of the wave with respect to the material direction.
Wave speed is commonly designated by the letter \( c \) (from the Latin celeritas meaning "velocity").