dy·​na·​mo | \ˈdī-nə-ˌmō \
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 1832 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, such as New York's legendary mayor Fiorello La Guardia, whose forcefulness and vigor matched that of his intensely dynamic city.

Examples of dynamo in a Sentence

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

Recent Examples on the Web

Awkwafina gets a fun breakout role, Rihanna is the essence of cool, but the real comedy dynamo here is Anne Hathaway, playing a persnickety parody of herself. Brian Truitt, USA TODAY, "Your ultimate Fourth of July movie guide: A suggestion for every holiday scenario," 29 June 2018 San Antonians on Monday mourned Edith McAllister, a tiny dynamo who left an indelible impact on every aspect of the city, from education to the arts to medicine. Carmina Danini And Melissa Fletcher Stoeltje, San Antonio Express-News, "McAllister remembered for her generosity, vitality," 2 July 2018 Freedom middle distance dynamo Timothy Doyle and Timber Creek pole vaulter Austin Thompson will seek to win state track and field championships on their future college campus at UNF in Jacksonville this weekend. Buddy Collings, OrlandoSentinel.com, "UNF signees Timothy Doyle, Austin Thompson pumped for state track and field," 4 May 2018 Conan Doyle, a Victorian dynamo with a walrus moustache and a passion for cricket and fair play, felt duty-bound to investigate. The Economist, "When Arthur Conan Doyle cried “J’Accuse…!”," 7 July 2018 The Danish dynamo's tenacious approach to midfield play makes him a prime candidate for Barça - who are in the market for a technically-gifted, creative midfielder. SI.com, "Spurs Line Up Huge Contract Extension for Pochettino as They Prepare for New White Hart Lane Era," 15 Feb. 2018 Within the last decade or so, industry dynamos such as Lee Boudreaux, Sarah Crichton and Reagan Arthur were all given their own imprints that featured their names on the spines. Lauren Mechling, Time, "Sarah Jessica Parker Is the Latest Celebrity to Start Her Own Book Imprint," 14 June 2018 Shero held up his end of the bargain by finding better players, acquiring defenseman Sami Vatanen from Anaheim last November, grabbing speedster Michael Grabner and below-the-net dynamo Patrick Maroon before the trade deadline. Alex Prewitt, SI.com, "Taylor Hall Raises the Bar for Himself, Devils in MVP-Caliber Season," 12 Apr. 2018 The 5-foot-11, 201-pound dynamo is tough, reliable, and explosive after the catch—and should take pressure off Larry Fitzgerald in the passing attack come fall. The Heat Index, azcentral, "NFL draft reaction: Arizona Cardinals among biggest winners in 2018 NFL draft?," 30 Apr. 2018

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 dynamoelectric machine

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Statistics for dynamo

Last Updated

3 Nov 2018

Look-up Popularity

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

: someone who has a lot of energy


dy·​na·​mo | \ˈdī-nə-ˌmō \
plural dynamos

Kids Definition of dynamo

1 : generator

2 : an energetic person

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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).


obstinately defiant of authority

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