Periodicity

Periodicity is the quality of occurring at regular intervals (e.g. of time) and can occur in different contexts:

• A clock marks time at periodic intervals.
• A metronome ticks at periodic intervals.
• A publication published at periodic intervals can be called a "periodical", though it can also be called magazine.
• In mathematics, a function which recurs periodically is called periodic function.
• In chemistry, a table which classifies elements by means of periodicity is the periodic table.

The measure of periodicity is frequency.

See also: synchronicity, simultaneity.