Ballast

Pronunciation

• RP IPA: /ˈbæl.É™st/
• Rhymes: -ælÉ™st

Origin

From Middle English bar ("bare") + last ("load").

Full definition of ballast

Noun

1. (nautical) Heavy material that is placed in the hold of a ship (or in the gondola of a balloon), to provide stability.
2. (figuratively) Anything that steadies emotion or the mind.
3. Coarse gravel or similar material laid to form a bed for roads or railroads, or in making concrete.
4. (construction) A material, such as aggregate or precast concrete pavers, which employs its mass and the force of gravity to hold single-ply roof membranes in place.
5. (countable, electronics) device used for stabilizing current in an electric circuit (e.g.in a tube lamp supply circuit)
6. (figurative) That which gives, or helps to maintain, uprightness, steadiness, and security.
• BarrowIt piety is the right ballast of prosperity.File:Hsin-chu-1.jpg|Ballast provides a supporting bed for rail tracksFile:Magnetic Ballasts 1.jpg|Several typical styles of magnetic ballasts for fluorescent lamps

Verb

1. To stabilize or load a ship with ballast.
2. To lay ballast on the bed of a railroad track.