flywheel

noun fly·wheel \ ˈflī-ˌhwēl , -ˌwēl \

|Updated on: 22 Jul 2018

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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Recent Examples of flywheel from the Web

McCloskey's 1920 Rumely Oil Pull tractor has to be started with a large flywheel on its side.

— mitchell kirk, Post-Tribune, "Cass County man collects tractors from around the world," 6 July 2018
The flywheels come in various sizes for monohull boats (sorry, no catamarans) from 25 feet to more than 85 feet long.

— jack stewart, WIRED, "Seakeeper’s Super Spinning System Keeps Ships Stable at Sea," 21 May 2018
Current satellites often rely on a type of flywheel called a reaction wheel.

— david grossman, Popular Mechanics, "Magnetic Engines Could Help Satellites Stay in Orbit Longer," 25 July 2016
Amazon’s frugality and high-tech investments in logistics create what analysts call a flywheel of ever-declining prices and delivery times.

— david whelan, chicagotribune.com, "What Amazon & Co. should fix first in our health care system," 27 Mar. 2018
From printing presses to the mechanics of manufacturing, the flywheel fostered our intellect and enabled our industry.

— bailey loosemore, The Courier-Journal, "Everything you want to know about Flywheel Brewing, a craft brewery in Kentucky," 4 Mar. 2018
Clean the Flywheel If your mower sees more than 4 hours of use a week or runs in dusty and dirty conditions, uncover the flywheel at midseason and brush off the fins with an old paintbrush.

— timothy dahl, Popular Mechanics, "How to Get Your Lawn Mower Ready for Spring," 8 Feb. 2018
Pushing it to two-thirds fires up the flywheels and starts the minigun rotation.

— david grossman, Popular Mechanics, "Watch This Nerf-Style Minigun Unleash Hell," 17 Jan. 2018
Amazon’s impact could be like when the Clinton Foundation moved into New York City’s Harlem in 2001, giving a hard push to a flywheel of renewal.

— kevin maney, Newsweek, "Big Tech: Hate Amazon, Apple, Facebook and Google? Get in Line," 6 Nov. 2017

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.

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.