flywheel

noun

fly·​wheel ˈflī-ˌ(h)wēl 

: 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)

Did you know?

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

Brands that effectively integrate technology into their customer experience (in a way that improves that experience) can begin to leverage 21st-century brand-building to keep their strategic flywheel turning. —Clifford Hudson, Forbes.com, 22 May 2026

The new reality finds those legacy players, with the single exception of Disney, playing defense as tech’s flywheel spins faster, and their pursuit of TV ad dollars becomes even more aggressive. —Alex Weprin, HollywoodReporter, 18 May 2026

When the deal was made two years ago, Apple needed to inject some cutting-edge AI into an aging Siri and OpenAI needed a Fortune 500-size flywheel to maintain its momentum as the leader of a new generation of AI startups. —Andrew Nusca, Fortune, 15 May 2026

The Japanese giant has apparently filed a patent for a motorcycle system that uses a fake clutch, a fake flywheel, and a set of vibration motors. —New Atlas, 14 May 2026

Word History

First Known Use

1784, in the meaning defined above

Rhymes for flywheel

• abele
• alkyl
• anneal
• appeal
• cartwheel
• conceal
• congeal
• coquille
• corneal
• cornmeal
• genteel
• handwheel

Kids Definition

flywheel

noun

fly·​wheel -ˌhwēl  -ˌwēl 

: a heavy wheel for regulating the speed of machinery