ballast

noun

bal·last | \ ˈba-ləst

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

ballast

verb

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

Alexis Taylor croons in a high, understanding tremble, and Joe Goddard offers plummy, sad ballast. — Spencer Kornhaber, The Atlantic, "Hot Chip Hones the Meaning of ‘Ecstasy’," 25 June 2019 The zebra mussel, which is native to Eastern Europe and Western Russia, made its way to Western Europe and the U.S. as a stowaway in ships' ballast water. — Christina Nunez, National Geographic, "Invasive species, explained," 5 June 2019 In fact, if moving down -- or even out -- could eliminate some of the onerous salary-cap ballast accumulated in recent years, then the Heat's selection on Thursday night might not come before 9 p.m., after all -- if at all. — Ira Winderman, sun-sentinel.com, "Unpredictability again enters into Heat’s NBA draft equation," 19 June 2019 The key informant, Salisbury said, was a sophisticated ship welder who hid cocaine in places where law enforcement hesitated to search, for fear of piercing the ballast and sinking ships in the river. — Rowan Moore Gerety, Harper's magazine, "Downstream," 10 June 2019 Its system treats ballast water while a ship is in transit. — Andrea Leinfelder, Houston Chronicle, "Katy-based Envirocleanse moves forward with ballast water treatment system," 7 June 2019 Some of his biggest detractors are hardline conservatives whose long practice at withstanding public blowback for their ideas gave them the ballast to make their disgust with Trump’s behavior known. — Ezra Klein, Vox, "The fall of the not-quite-Trumpers," 6 Nov. 2018 The pathways that trellised the fragrant herb garden outside the chatelaine’s bedroom and in the far-flung potager were made from bricks imported by the British, who used them as ballast for their ships. — Hamish Bowles, Vogue, "Inside Tory Burch’s Lovingly Restored Antigua Getaway," 15 Aug. 2018 Without power to control the pumps or control the filling of the ballast tanks, the dry dock completely submerged. — Sean Gallagher, Ars Technica, "Russia’s only aircraft carrier damaged as its floating dry dock sinks," 30 Oct. 2018

Recent Examples on the Web: Verb

Roughly a third of the structure is submerged and ballasted by 5,000 tons of iron ore. — Michael J. Coren, Quartz, "Floating wind farms just became a serious business," 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, "The Preposterous World of Human-Powered Submarine Racing," 9 Aug. 2017 Seawater ballasts help with stability and the horizontal surface is layered in solar panels and antennas. — Bill Monroe, OregonLive.com, "Oregon tag holders asked/required to report hunting, fishing results," 11 Jan. 2018 Seawater ballasts help with stability and the horizontal surface is layered in solar panels and bristles with antennas and a small wind generator. — Bill Monroe, OregonLive.com, "Local boat builder helps rower reach his ambition: Cross the Pacific Ocean," 5 Jan. 2018 Heritage-Crystal Clean contracted with Huston Electric to retrofit the light ballasts with LED fixtures. — Carole Carlson, Post-Tribune, "Industry fines help fund upgrades at Gary schools," 23 Oct. 2017

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.