periodic

adjective pe·ri·od·ic \ ˌpir-ē-ˈä-dik \

Definition of periodic

1 a :occurring or recurring at regular intervals

b :occurring repeatedly from time to time

2 a :consisting of or containing a series of repeated stages, processes, or digits :cyclic

periodic decimals

a periodic vibration

b :being a function any value of which recurs at regular intervals

3 :expressed in or characterized by periodic sentences

See periodic defined for English-language learners

See periodic defined for kids

Examples of periodic in a Sentence

He takes the car in for periodic oil changes.
sent out periodic reminders about the office dress code

Recent Examples of periodic from the Web

Further bloodshed in the capital, the site of periodic eruptions of violence since the conflict began in December 2013, would imperil attempts to revive an economy that has sub-Saharan Africa’s third-biggest oil reserves.

— okech francis, Bloomberg.com, "Crime Wave Stalks South Sudan's Capital as War Ruins Economy," 23 Aug. 2017
It’s more than a school subject, or the periodic table, or the properties of waves.

— rebecca boyle, The Atlantic, "Will Trump Take Notice of the Eclipse?," 17 Aug. 2017
But periodic dividing is important for maintaining plant health.

— dennis patton, kansascity, "Time to divide the iris," 4 Aug. 2017
After being subject to the president’s periodic attempts to rally support for the various repeal bills, some perplexed lawmakers suggested Mr Trump did not seem to understand them.

— The Economist, "Not repealing Obamacare," 20 July 2017
This is your periodic reminder that Criminal Justice Reform is going to be the big bipartisan issue that brings our divided nation together.

— charles p. pierce, Esquire, "Jeff Sessions, Civil Forfeiture, What Could Go Wrong?," 18 July 2017
On-shore flow may give residents along the lake periodic reprieves.

— tom skilling, chicagotribune.com, "Hot, humid weather arrives; heat hits hard downstate," 18 July 2017
Periodical cicadas are broken into two groups based on its 17 or 13-year periodic appearances.

— jefferson county cooperative extension, AL.com, "Danger follows the buzz of summer (Garden Talk)," 18 July 2017
Heal the Bay, which posts periodic report cards on water quality along the California coast, had noted some dramatic improvements in 2016—until the history-making storms hit.

— ann herold, Los Angeles Magazine, "These Photos Will Make You Fall in Love with LA’s Beaches All Over Again," 17 July 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'periodic.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of periodic

1650

periodic Synonyms

Synonyms

constant, frequent, habitual, regular, periodical, repeated, steady

Antonyms

inconstant, infrequent, irregular

Related Words

continual, intermittent, recurrent, recurring; cyclic (or cyclical); around-the-clock, hourly, round-the-clock, 24-7 (or 24/7); chronic, confirmed, inveterate; expected, usual

Near Antonyms

episodic (also episodical), occasional; unexpected, unusual

Other Mathematics and Statistics Terms

abscissa, denominator, divisor, equilateral, exponent, hypotenuse, logarithm, oblique, radii, rhomb

PERIODIC Defined for English Language Learners

periodic

adjective

Definition of periodic for English Language Learners

: happening regularly over a period of time

PERIODIC Defined for Kids

periodic

adjective pe·ri·od·ic \ ˌpir-ē-ˈä-dik \

Definition of periodic for Students

:occurring regularly over a period of time

Medical Dictionary

periodic

adjective pe·ri·od·ic \ ˌpir-ē-ˈäd-ik \

medical Definition of periodic

:occurring or recurring at regular intervals

periodic epidemics

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periodic

Definition of periodic

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Examples of periodic in a Sentence

Recent Examples of periodic from the Web

First Known Use of periodic

periodic Synonyms

Synonyms

Antonyms

Related Words

Near Antonyms

Other Mathematics and Statistics Terms

PERIODIC Defined for English Language Learners

periodic

Definition of periodic for English Language Learners

PERIODIC Defined for Kids

periodic

Definition of periodic for Students

Medical Dictionary

periodic

medical Definition of periodic

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