Definition of ballast
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)
of a ship : having only ballast for a load
Recent Examples of ballast from the Web
The Italian railway said vibrations from the train have no impact on adjacent buildings because they are absorbed by ballast.
These creatures likely made their way here in ballast water from freighter ships traveling from Europe in the mid-1980s.
They are believed to have made their way to North America in the 1980s inside the ballast water of ships.
Alaina Mills (pinch-hitting on opening night) and Ben Fankhauser provide comic ballast as friends, fellow tunesmiths and rivals Cynthia Weil and Barry Mann, coming together even as King and Goffin fall apart.
A 4.9 percent holding of Berkshire Hathaway Inc. provides some ballast and rounds out the top five holdings, bringing them to a little more than 26 percent of the fund.
Will Smith gave Suicide Squad A-list ballast as Deadshot.
The boat stays in place via anchors and is weighed down by the ballast.
But sometime after that, the suit claims, the school raised additional money and installed four 70-foot-tall poles with nine ballasts on each pole.
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.
BALLAST Defined for English Language Learners
Definition of ballast for English Language Learners
: heavy material (such as rocks or water) that is put on a ship to make it steady or on a balloon to control its height in the air
BALLAST Defined for Kids
Definition of ballast for Students
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
Seen and Heard
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