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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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 Not in the market for a dynamo of a home workstation? Brittany Vincent, CNN Underscored, "Prep for the new school year with these one-day Apple deals at Woot!," 9 July 2020 Meredith’s shocking move to comfortable grounding character — rather than explosive, narrative-pushing dynamo — begins slowly over the 22 episodes of Grey’s Anatomy season 16. Ariana Romero, refinery29.com, "Grey’s Anatomy Season 16 Is Now On Netflix. Is Meredith Grey Still its Star?," 9 May 2020 Nichols has reported finding magnetic fields in 3.7-billion-year-old rocks from Greenland—another sign of an early magnetic dynamo on Earth. Paul Voosen, Science | AAAS, "Diamond microscope reveals slow crawl of Earth’s ancient crust," 22 Apr. 2020 Soon to be among the NFL's slight receivers at 5-9 and 178 pounds, Hamler will make his mark as a deep-threat dynamo and slot target who can rack up yards after the catch, so long as he's not beset by the drops that plagued his college career. Michael Middlehurst-schwartz, USA TODAY, "NFL draft 2020 rankings: Chase Young, Joe Burrow headline top 50 rankings," 14 Apr. 2020 Not even six months removed from his last leukemia treatment, the wiry guard has grown into a 3-point dynamo and go-to closer. Nick Moyle, ExpressNews.com, "Backs against the wall, surging Texas gets another shot at No. 22 Texas Tech," 28 Feb. 2020 From the #empowHER hashtag written on every mirror and surface, to the dozens of female musicians, industry dynamos and more attendees engaging in encouraging conversation, the love in the air was certainly felt. Rania Aniftos, Billboard, "Facebook & Instagram Honor Today's Most Inspiring Female Executives at Women in Music Pre-Grammy Lunch," 24 Jan. 2020 The problem is that Scanlan and Marshall give us a one-note dynamo whose needle never leaves a positively aggressive red zone. New York Times, "Review: ‘The Unsinkable Molly Brown’ Has Its Ups and Ups," 26 Feb. 2020 Ancient magnetism Mars is thought to have once had a magnetic dynamo at its core, much like Earth's. John Timmer, Ars Technica, "Marsquakes and ancient magnetic fields: InSight’s first data," 25 Feb. 2020

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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Time Traveler for dynamo

Time Traveler

The first known use of dynamo was in 1882

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Statistics for dynamo

Last Updated

17 Jul 2020

Cite this Entry

“Dynamo.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/dynamo. Accessed 8 Aug. 2020.

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More Definitions for dynamo


How to pronounce dynamo (audio)

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

2 : an energetic person

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More from Merriam-Webster on dynamo

Thesaurus: All synonyms and antonyms for dynamo

Rhyming Dictionary: Words that rhyme with dynamo

Spanish Central: Translation of dynamo

Nglish: Translation of dynamo for Spanish Speakers

Britannica.com: Encyclopedia article about dynamo

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