bal·​last | \ ˈba-ləst How to pronounce ballast (audio) \

Definition of ballast

 (Entry 1 of 2)

1 : a heavy substance (such as rocks or water) placed in such a way as to improve stability and control (as of the draft of a ship or the buoyancy of a balloon or submarine) tossed several tons of ballast overboard
2 : something that gives stability (as in character or conduct) She provided the ballast we needed during stressful times.
3 : gravel or broken stone laid in a railroad bed or used in making concrete
4 : a device used to provide the starting voltage or to stabilize the current in a circuit (as of a fluorescent lamp)
in ballast
of a ship : having only ballast for a load


ballasted; ballasting; ballasts

Definition of ballast (Entry 2 of 2)

transitive verb

1 : to steady or equip with or as if with ballast They ballast the canoe with large rocks.
2 : to fill in (something, such as a railroad bed) with ballast (see ballast entry 1 sense 3)

Examples of ballast in a Sentence

Recent Examples on the Web: Noun Accommodation provides a little ballast against start-up costs and can be flexibly used for pickers during harvest. Sarah Turner, Forbes, 31 May 2021 Still, the statements by Russian officials underscored a striking effort to woo a country that is seen by Moscow as a crucial diplomatic ballast against the rising tide of Western condemnation and sanctions. Washington Post, 1 Mar. 2022 No matter how harsh the storm, Powell’s ballast kept him from getting knocked down or blown off course. Christopher Burnham, Forbes, 18 Oct. 2021 So Bynum kept trying to find new ways to bring the credit union ballast—in the form of large deposits from wealthier players in the economy. Victor Luckerson, Wired, 5 Oct. 2021 On that superlative show, the TV stars are realtors, which lends structure and ballast to their endless playing for camera time. Daniel D'addario, Variety, 6 Jan. 2022 Strolling along cobblestone streets, Rodriguez explains that the stones were used as ballast for arriving ships before becoming the early roads. Patricia Doherty, Travel + Leisure, 29 Sep. 2021 The offensive outburst finished as a 63-10 romp that should give head coach Jim Harbaugh and coordinator Josh Gattis more confidence as the passing attack offers ballast to a run-first offense. Michael Cohen, Detroit Free Press, 18 Sep. 2021 In the end, Goran Dragic has turned into nothing more than 35-year-old salary-cap ballast for the Toronto Raptors, the cost of acquiring Precious Achiuwa in the sign-and-trade with the Heat for Kyle Lowry. Ira Winderman,, 6 Nov. 2021 Recent Examples on the Web: Verb The species, which grows to 6 feet long and weighs up to 220 pounds, was prized for its swim bladder, or maw, an organ that helps ballast the animal. Adam Elder, Wired, 16 Apr. 2020 Amid that debate, the role of the editorial board is to provide Times readers with a long-range view formed not by one person’s expertise and experience but ballasted by certain institutional values that have evolved across more than 150 years. New York Times, 13 Jan. 2020 Some of that freshness comes from the cast, a cornucopia of effervescent young talent ballasted by a handful of doughty old-timers. New York Times, 23 Dec. 2019 Gillis said the new bridge will be ballasted, rather than fixed. Mary Wisniewski,, 21 Aug. 2019 Green Bay’s unbalanced and condensed formations, presnap motions, first-down play-actions and intertwined route combinations play to Rodger’s sharp football IQ, ballasting his reads and timing. Andy Benoit,, 23 July 2019 Roughly a third of the structure is submerged and ballasted by 5,000 tons of iron ore. Michael J. Coren, Quartz, 22 June 2019 The subs are built from a variety of materials, but primarily plastics, carbon fiber, and other composites, with a few metal components and some weights to ballast the vessel. Jay Bennett, Popular Mechanics, 9 Aug. 2017 Seawater ballasts help with stability and the horizontal surface is layered in solar panels and antennas. Bill Monroe,, 11 Jan. 2018 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'ballast.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of ballast


15th century, in the meaning defined at sense 1


1538, in the meaning defined at sense 1

History and Etymology for ballast

Noun and Verb

probably from Low German, of Scandinavian origin; akin to Danish & Swedish barlast ballast; perhaps akin to Old English bær bare & to Old English hlæst load, hladan to load — more at lade

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Time Traveler for ballast

Time Traveler

The first known use of ballast was in the 15th century

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Statistics for ballast

Last Updated

14 May 2022

Cite this Entry

“Ballast.” Dictionary, Merriam-Webster, Accessed 19 May. 2022.

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More Definitions for ballast


bal·​last | \ ˈba-ləst How to pronounce ballast (audio) \

Kids Definition of ballast

1 : heavy material used to make a ship steady or to control the rising of a balloon
2 : gravel or broken stone laid in a foundation for a railroad or used in making concrete


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