frequency

noun (plural frequencies)

• 1 [mass noun] the rate at which something occurs over a particular period of time or in a given sample:an increase in the frequency of accidents due to increased overtime
• the fact or state of being frequent or happening often.

• 2the rate per second of a vibration constituting a wave, either in a material (as in sound waves), or in an electromagnetic field (as in radio waves and light):different thicknesses of glass will absorb different frequencies of sound (Symbol: f or ν)
• the particular waveband at which radio signals are broadcast or transmitted: a radio station on a single AM radio frequency [mass noun]:a coding sequence to ensure that everyone changes frequency in the correct manner