noun bal·last \ˈba-ləst\

: 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

Full Definition of BALLAST

:  a heavy substance 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)
:  something that gives stability (as in character or conduct)
:  gravel or broken stone laid in a railroad bed or used in making concrete
:  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

Origin of BALLAST

probably from Low German, of Scandinavian origin; akin to Dan & Swedish barlast ballast; perhaps akin to Old English bær bare & to Old English hlæst load, hladan to load — more at lade
First Known Use: 1530

Other Civil Engineering Terms

asphalt, barrage, cantilever, infrastructure, sluice

Rhymes with BALLAST



Definition of BALLAST

transitive verb
:  to steady or equip with or as if with ballast
:  to fill in (as a railroad bed) with ballast

First Known Use of BALLAST

IN BALLAST Defined for Kids


noun bal·last \ˈba-ləst\

Definition of BALLAST for Kids

:  heavy material used to make a ship steady or to control the rising of a balloon
:  gravel or broken stone laid in a foundation for a railroad or used in making concrete


Next Word in the Dictionary: ballastagePrevious Word in the Dictionary: ballasAll Words Near: ballast
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