Frequency
A sound wave emanates from a source vibrating at a frequency f, propagates at v, and has a wavelength λ.
Source
Boundless vets and curates high-quality, openly licensed content from around the Internet. This particular resource used the following sources:
"OpenStax College, Speed of Sound, Frequency, and Wavelength. December 23, 2012."
http://cnx.org/content/m42256/latest/
OpenStax CNX
CC BY 3.0.