dy·​na·​mo | \ ˈdī-nə-ˌmō How to pronounce dynamo (audio) \
plural dynamos

Definition of dynamo

2 : a forceful energetic individual

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Synonyms for dynamo


fireball, live wire, pistol

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Did You Know?

The dynamo was introduced in 1867 to produce electricity for commercial use. Like all later generators, the original dynamos changed mechanical energy (produced by steam, which was itself produced by burning coal) into electricity. The word is less used today than it once was, since it's often applied only to generators that produced direct electric current (DC) rather than alternating current (AC), which is now the standard. A human dynamo is a person who seems to have unlimited energy.

Examples of dynamo in a Sentence

a dynamo who barely needs to sleep, or so it seems

Recent Examples on the Web

And no one in its long history rebuilt more than Amedeo Maiuri, a human dynamo, who, as superintendent from 1924 to 1961, directed digs during some of Italy’s most trying times. Chiara Goia, Smithsonian, "The New Treasures of Pompeii," 21 Aug. 2019 Ginobili was the selfless, daring dynamo who captured the hearts and imagination of San Antonio’s Hispanic fan base. Jeff Mcdonald, ExpressNews.com, "Spurs’ Big Three reunited in retirement as Tony Parker hangs it up," 10 June 2019 Instead, these four-legged dynamos compete on their lack of cuteness all in an effort to win the title of World's Ugliest Dog. Hollie Silverman, CNN, "Watch out world, a new ugliest dog has been crowned," 24 June 2019 But Jones quickly realized his quickest route to the 53-man rosters was first developing into a special teams dynamo. Kyle Fredrickson, The Denver Post, "Broncos’ rookie Josh Watson eager for NFL preseason debut: “The man wants to hit constantly”," 1 Aug. 2019 The same can be said of the lineup, with Betts serving as a top-of-the-order dynamo. Alex Speier, BostonGlobe.com, "Chris Sale, Mookie Betts showing what they’re capable of," 18 July 2019 The front light is wired to a separate front-hub dynamo, not the battery. Thomas Ricker, The Verge, "Byar Volta is a shaft-driven e-bike that might never need charging," 17 July 2019 The speedster and lifelong offensive dynamo was asked to transition to playing cornerback. David Furones, sun-sentinel.com, "How former FAU standout and ‘Last Chance U’ star John Franklin III is making his mark with Chicago Bears," 2 July 2019 Wide, 47mm tires make transitioning from pavement to unpaved paths easy and fun, while front and rear light, powered by a dynamo in the front hub, and reflective decals on the frame help the rider see and be seen. Bradley Ford, Popular Mechanics, "The Best Commuter Bikes for Any Commute," 16 May 2019

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

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First Known Use of dynamo

1882, in the meaning defined at sense 1

History and Etymology for dynamo

short for dynamo-electric machine, translation of German dynamo-elektrische Maschine; dynamo-elektrisch, probably by inversion of elektrodynamisch electrodynamic

Note: According to the Oxford English Dictionary (1st edition, 1897), "The full name dynamo-electric machine was given by [Werner] Siemens in 1867, to distinguish his invention from the magneto-electric machines previously used, in which the electric current was generated by means of a permanent magnet." This statement appears to be based on a citation from The Times (December 5, 1882), according to which, "Professor Thompson [not further identified] said that the name 'dynamo-electric machine' was first applied by Dr. Werner Siemens in a communication made in January, 1867, to the Berlin Academy." The communication in question was "Ueber die Umwandlung von Arbeitskraft in elektrischen Strom ohne Anwendung permanenter Magnete," published in Annalen der Physik und Chemie, Band 130 (1867), pp. 332-35. The article does in fact describe a generator with rotating coils, but nowhere does Siemens use the word dynamo-elektrisch or the phrase dynamo-elektrische Maschine; the closest he comes is magnetelektrisch for the opposing term. The first appearance of dynamo-elektrisch must date some time after this.

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Statistics for dynamo

Last Updated

17 Sep 2019

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Time Traveler for dynamo

The first known use of dynamo was in 1882

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More Definitions for dynamo



English Language Learners Definition of dynamo

: a machine that produces electricity
informal : someone who has a lot of energy


dy·​na·​mo | \ ˈdī-nə-ˌmō How to pronounce dynamo (audio) \
plural dynamos

Kids Definition of dynamo

1 : generator
2 : an energetic person

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More from Merriam-Webster on dynamo

Rhyming Dictionary: Words that rhyme with dynamo

Thesaurus: All synonyms and antonyms for dynamo

Spanish Central: Translation of dynamo

Nglish: Translation of dynamo for Spanish Speakers

Britannica.com: Encyclopedia article about dynamo

Comments on dynamo

What made you want to look up dynamo? Please tell us where you read or heard it (including the quote, if possible).


to make a temporary encampment

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