frequency
FREE-kwun-see
/ˈfriːkwənsi/
The number of complete cycles or oscillations of an alternating wave or current per unit of time (measured in Hertz).
Determines wave properties like pitch in audio, color in optics, and channel band in radio.
The story behind the word. From Latin 'frequentia', meaning a crowd or repeated occurrence. In physics, Heinrich Hertz demonstrated wave cycles per second, later named Hertz in his honor.
Word relationships
- pitch: Pitch is the subjective human perception of sound frequency, whereas frequency is the objective physical cycle rate.
- period: Period is the time required for one full cycle, making it the mathematical inverse of frequency.
Commonly confused with
- wavelength: Frequency measures cycles per second, whereas wavelength measures spatial distance between wave crests.
Word family
- frequent (adjective): Occurring often.
- frequentative (adjective): Expressing repeated action.
Collocations
- high frequency
- radio frequency
- resonant frequency
- frequency modulation
Example sentences
- "North American power grids operate at a standard AC frequency of 60 Hertz." Power grid operation standards
- "Wi-Fi routers transmit data using radio frequency bands centered around 2.4 GHz and 5 GHz." Wireless communication setup
Memory hook
HOW FREQUENTLY does the wave cycle repeat? Cycles per second in wave motion.
When not to use
Do not confuse cycle frequency (Hertz) with simple event counts that lack continuous periodic timing.
Fun facts
- Visible light ranges in frequency from 400 trillion Hertz (red) to 780 trillion Hertz (violet).
Related words
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