Definition of ballast in English:

ballast

Syllabification: bal·last
Pronunciation: /ˈbaləst
 
/

noun

1Heavy material, such as gravel, sand, iron, or lead, placed low in a vessel to improve its stability.
More example sentences
  • Many ships discharge their ballast and bilge during loading and unloading because many Black Sea ports lack reception facilities.
  • The bilges are firm and ballast is low which makes for a stiff boat that stands up well to a blow.
  • The shells could have been brought back as ballast on ships or collected by sailors or travelers for their wives, daughters, or friends.
1.1Heavy material carried in an airship or on a hot-air balloon to stabilize it, and jettisoned when greater altitude is required.
More example sentences
  • It is obvious that the ‘cancer’ shields were actually invented to add weight to phones in order that they would be more effective when used as ballast in hot air balloons.
  • Either he carries more ballast, or his glider/harness has less drag than the ATOS C with me or Johann on it.
  • It's almost twice as heavy as lead, so it's great for armour plating, radiation shielding, ballast in missiles and aircraft counterweights.
1.2Something that gives stability or substance: the film is an entertaining comedy with some serious ideas thrown in for ballast
More example sentences
  • Start trotting out the same lines, the same solutions and, rather than tapping into a source of riches, you're carrying ballast about with you and you'll soon be buried beneath it.
  • So, we felt that if Young and Macuga could draw on Taipei's urban environment this would act as local cultural ballast or a visual counter-balance to these other works.
  • Without further preamble here is my own preliminary list of threads that we can snip away at, the ballast that we can jettison in the coming months.
2Gravel or coarse stone used to form the bed of a railroad track or road.
More example sentences
  • Some 97,000 tonnes of stone were transported in and 10,000 tonnes of ballast laid along the track bed.
  • The area developed with the founding of the town of Katoomba in the 1860s to supply quarried ballast to the railways.
  • They are also used, to a more limited extent, for railway ballast.
2.1A mixture of coarse and fine aggregate for making concrete.
More example sentences
  • To transfer the weight of the ballast and the box girder to the longitudinal central beam that anchors the stays, vertical posttensioning has been provided in the fin walls.
  • As well, Mr. MacAdam confirms that he advised the plaintiffs to engage a roofing consultant to give an opinion on the adequacy of the roof flashings and the roofing ballast.
  • It was built from a combination of heavyweight concrete and steel ballast to develop the required weight.
3A passive component used in an electric circuit to moderate changes in current.
More example sentences
  • The third electrode may be biased at the potential of the anode through a ballast resistor, and be located near the cathode.
  • They also operate 75% more quietly than do conventional electromagnetic ballasts, eliminating the familiar flicker and hum of older fluorescent lights.
  • Along with the EMCS, the renovation introduced energy-efficient task lighting and electronic ballasts for all workstation lighting.

verb

[with object] (usually be ballasted) Back to top  
1Give stability to (a ship) by putting a heavy substance in its bilge: the vessel has been ballasted to give the necessary floating stability
More example sentences
  • Flooding of the docking area is achieved by ballasting the stern of the ship, allowing the landing craft to float.
  • The Eide Transporter was ballasted down with water until her transport deck was below water.
  • ‘Each tube will be set in a lay barge, ballasted and lowered with winches,’ says DelGrosso.
2Form (the bed of a railroad line or road) with gravel or coarse stone.
More example sentences
  • Even if it had been told that Soviet Railways ballasted thousands of miles of track with asbestos waste it would not have cared.
  • Another way was to ballast the train with additional cars, so that the locomotive speed would stabilize at a single value.
  • When we were done there, we all moved back south of the crossing and began to surface the track in that area, which we had ballasted during the spring trackwork session last April.

Origin

mid 16th century: probably of Low German or Scandinavian origin.

Phrases

in ballast

(Of a ship) laden only with ballast.
More example sentences
  • Taking a ship in ballast from the Mersey to the Tyne around Scotland was never the best of voyages.
  • Having left Antwerp in ballast the 2000 ton ship was making her way to New York.
  • When wrecked, she was travelling in ballast with her four holds empty from her home port of Aarhus, Denmark, bound for Newcastle-upon-Tyne to pick up a general cargo.

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excessive pride or self-confidence