fly·​wheel | \ ˈflī-ˌhwēl How to pronounce flywheel (audio) , -ˌwēl How to pronounce flywheel (audio) \

Definition of flywheel

: a heavy wheel for opposing and moderating by its inertia any fluctuation of speed in the machinery with which it revolves also : a similar wheel used for storing kinetic energy (as for motive power)

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A heavy wheel attached to a rotating shaft, a flywheel smooths out delivery of power from a motor to a machine. The inertia of the flywheel moderates fluctuations in the speed of the engine and stores the excess energy for intermittent use. In automobile engines, the flywheel smooths out the pulses of energy provided by combustion in the cylinders, and provides energy for the compression stroke of the pistons. In power presses, the punching, shearing, and forming are done in a fraction of the operating cycle. During the rest of the cycle, the speed of the flywheel is built up by a comparatively low-powered motor, and most of the required energy for the cycle is provided by the flywheel.

Examples of flywheel in a Sentence

Recent Examples on the Web

The Pista sheds nearly 200 pounds compared with the standard 488 GTB road car—almost 40 pounds from the engine alone (titanium con-rods, lightweight flywheel). Dan Neil, WSJ, "I Drove a Screaming Fast Ferrari Among Ordinary Cars," 21 Feb. 2019 The flywheel gives pedaling a realistic sense of inertia. James Lynch, Popular Mechanics, "PM Approved: Kickr Smart Bike Trainer," 29 Jan. 2019 Second, the goal is a flywheel, or virtuous circle. Steven A. Cohen And, WSJ, "Models Will Run the World," 19 Aug. 2018 The Verge explores the latest developments in energy storage, from those giant batteries to infinitely spinning flywheels to bottling gas in underground caverns. Angela Chen, The Verge, "Why the future of the power grid depends on giant batteries," 14 Aug. 2018 The brainchild of Brendan McCarthy, a Long Island fishing guide, this new kid on the block comes with a V-bar grate that raises and lowers with a flywheel. Steven Raichlen, New York Times, "Cooking Over Wood: A Guide to the Grills," 29 June 2018 Although economic flywheels played an important role, the story of how the internet became centralised is more complex. The Economist, "More knock-on than networkThe story of the internet is all about layers," 28 June 2018 As a boat rolls, the angular momentum of the flywheel creates a reaction force that transmits through the mounts to the hull of the boat. Dan Neil, WSJ, "Skip the Seasickness: How Boats Are Getting More Tech-Savvy," 28 June 2018 The resulting rotation engages the flywheel, turning the engine over. Kevin Dupzyk, Popular Mechanics, "Watch Us Take Apart a Chainsaw Into 297 Pieces," 24 June 2015

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'flywheel.' 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 flywheel

1784, in the meaning defined above

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Dictionary Entries near flywheel





fly whisk



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Last Updated

27 May 2019

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Time Traveler for flywheel

The first known use of flywheel was in 1784

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English Language Learners Definition of flywheel

: a heavy wheel that is part of a machine and that controls the speed of machinery

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More from Merriam-Webster on flywheel

Rhyming Dictionary: Words that rhyme with flywheel

Spanish Central: Translation of flywheel

Nglish: Translation of flywheel for Spanish Speakers Encyclopedia article about flywheel

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