- A unit of frequency equal to one cycle per second.
- a unit of frequency equal to one cycle per second; it is abbreviated Hz. It is commonly used to specify the frequency of radio waves, and also the clock frequencies in digital computers. For these applications, kilohertz and megahertz are the most commonly used units, derived from <ex>hertz</ex>.
- In the <xref>International System of Units</xref>, the <xref>derived unit</xref> of <xref>frequency</xref>; one (<xref>period</xref> or cycle of any <xref>periodic</xref> event) per <xref>second</xref>. Symbol: <xref>Hz</xref>
- German physicist who with James Franck proved the existence of the stationary energy states postulated by Bohr (1887-1975)
- the unit of frequency; one hertz has a periodic interval of one second
- German physicist who was the first to produce electromagnetic waves artificially (1857-1894)