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

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 Onboard mechanisms pump water into ballast tanks that weigh down the boat and augment the wake. — Jen Murphy, WSJ, "It’s Surfing, Without the Hard Spills—And in Wisconsin," 4 Aug. 2018 Carrying important cargo that is hefty enough to keep my versatile vessel from being able to take off, I’m left with two choices: flee or dump the ballast to turn and fight. — Daniel Starkey, Ars Technica, "Starlink: Battle for Atlas review: Cool toys, solid spacefaring," 16 Oct. 2018 With his connections in the Justice Department and his prosecutorial chops, Mr. Giuliani adds some ballast to a legal team that is currently composed of lesser lights. — New York Times, "In Defending Trump, Giuliani Will Lean on His Rolodex and Reputation," 20 Apr. 2018 Either hat could be ballast for that other current Jacquemus best-seller, the teensy Sac Chiquito handbag. — Linda Dyett, The Seattle Times, "Hats are big this summer. Really, really big," 16 Aug. 2018 Truly ancient wrecks like this one usually leave behind only a scattering of amphorae, ballast stones, or broken pottery on the seafloor to tell the tale. — Kiona N. Smith, Ars Technica, "This ancient Greek ship is the oldest intact shipwreck ever discovered," 24 Oct. 2018 The outage caused the drydock’s ballast tanks to fill rapidly, sinking the entire thing. — Kyle Mizokami, Popular Mechanics, "Russia’s Hard-Luck Carrier Damaged in Shipyard Accident," 30 Oct. 2018

Recent Examples on the Web: Verb

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.