View synonyms for ballast


[ bal-uhst ]


  1. Nautical. any heavy material carried temporarily or permanently in a vessel to provide desired draft and stability.
  2. Aeronautics. something heavy, as bags of sand, placed in the car of a balloon for control of altitude and, less often, of attitude, or placed in an aircraft to control the position of the center of gravity.
  3. anything that gives mental, moral, or political stability or steadiness:

    the ballast of a steady income.

  4. gravel, broken stone, slag, etc., placed between and under the ties of a railroad to give stability, provide drainage, and distribute loads.
  5. Electricity.
    1. Also called bal·last re·sis·tor [bal, -, uh, st ri-zis-ter]. a device, often a resistor, that maintains the current in a circuit at a constant value by varying its resistance in order to counteract changes in voltage.
    2. a device that maintains the current through a fluorescent or mercury lamp at the desired constant value, sometimes also providing the necessary starting voltage and current.

verb (used with object)

  1. to furnish with ballast:

    to ballast a ship.

  2. to give steadiness to; keep steady:

    parental responsibilities that ballast a person.


/ ˈbæləst /


  1. any dense heavy material, such as lead or iron pigs, used to stabilize a vessel, esp one that is not carrying cargo
  2. crushed rock, broken stone, etc, used for the foundation of a road or railway track
  3. coarse aggregate of sandy gravel, used in making concrete
  4. anything that provides stability or weight
  5. electronics a device for maintaining the current in a circuit


  1. to give stability or weight to

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Other Words From

  • bal·last·er noun
  • bal·last·ic [b, uh, -, las, -tik], adjective
  • o·ver·bal·last verb (used with object)
  • sub·bal·last noun
  • un·der·bal·last verb (used with object)

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Word History and Origins

Origin of ballast1

1450–1500; < Middle Low German, perhaps ultimately < Scandinavian; compare Old Danish, Old Swedish barlast, equivalent to bar bare 1 + last load; last 4

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Word History and Origins

Origin of ballast1

C16: probably from Low German; related to Old Danish, Old Swedish barlast , literally: bare load (without commercial value), from bar bare, mere + last load, burden

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Idioms and Phrases

  1. in ballast, Nautical. carrying only ballast; carrying no cargo.

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Example Sentences

In particular, it had very dense leg bones, a feature of some aquatic creatures like manatees that need the bones for ballast to stay submerged.

Other options include dredging around the ship and offloading ballast water, fuel, or cargo.

From Time

While not exactly the Ugly American, Sinatra provided plenty of his own homegrown ballast.

Especially the Southern ones, who by and large run the party, or at least provide its cultural ballast.

“Gold lost its structural ballast when it lost its formal relationship to money,” he concludes.

Straighten up and fly right: the capsule is rolling and jettisoning its remaining ballast masses for parachute deploy.

Spin down, turn to entry attitude and jettison ballast mass in one minute.

Sand and gravel are also used for "fill," for engine sands, railroad ballast and glass.

Old and new measurements, tonnage, time allowances and movable ballast, are all a sealed book to me.

The big sloop, hard aground and full of iron ballast, was not a thing to be moved easily.

Our new craft worked and sailed well, after a little addition of ballast.

I ordered the ballast to be thrown overboard, and determined, as our only chance, to attempt to force her over the reef.


Related Words

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More About Ballast

What does ballast mean?

In general, ballast means something that provides stability or weight.

In a specific sense, it’s most commonly used to refer to heavy material used to stabilize a vessel, such as a ship, especially when it’s not carrying cargo. It also refers to the crushed rock used for the foundation of railroad tracks and paved roads. In electronics, ballast refers to a device that maintains the current in a circuit.

Ballast can also be used as a verb meaning to provide a ship with a material for ballast. In a more general sense, it can mean to keep steady or give stability to, including in a metaphorical way. Ballast can also be used metaphorically as a noun, especially in the context of mental, emotional, political, or economic stability.

Example: The ship’s ballast was improperly secured and caused the ship to list in the water.

Where does ballast come from?

The first records of ballast come from the 1400s. It comes from Middle Low German and is related to the Old Swedish word barlast, which literally means “bare load.”

When a ship is fully loaded with cargo, the weight of the cargo helps the ship to be stable in the water. Without cargo, it needs ballast. This can take many forms, such as stones or lead. (Sometimes, ballast is a permanent feature of a ship, such as a ballast tank that holds water.) In smaller vessels, the crew members themselves might suffice as ballast (called live ballast). Ballast is not limited to ships. In hot air balloons, those bags of sand attached to the car (the basket) are ballast.

Have you ever noticed the layer of stones under railroad tracks? They’re there for ballast, to provide the foundation for the track (gravel or crushed rock is also used as ballast in the base layer of a paved road). In a railroad track, the stone ballast helps with drainage and prevents plants from growing inside the tracks, too.

Ballast can also be used in a figurative way to refer to something that provides balance or stability in life or a specific situation, as in It helps to have a hobby to act as ballast during stressful times.

Did you know ... ?

What are some other forms related to ballast?

  • ballaster (noun)
  • ballastic (adjective)
  • overballast (verb)
  • subballast (noun)

What are some synonyms for ballast?

What are some words that share a root or word element with ballast


What are some words that often get used in discussing ballast?


How is ballast used in real life?

You’ll most often see ballast used in the context of ships and other vessels. Unless it’s used metaphorically, it’s typically discussed in a technical way.



Try using ballast!

Is ballast used correctly in the following sentence?

The ballast keeps the hot air balloon stable so it can be better controlled while in the air.

Definitions and idiom definitions from Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.




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