A stabilizing unit that regulates the flow of electricity and starts an High-Intensity Discharge (HID) lamp – a ballast consists of a transformer and a capacitor.
Ballast is dense material used as a weight to provide stability to a vehicle or structure. Ballast, other than cargo, may be placed in a vehicle, often a ship or the gondola of a balloon or airship, to provide stability. A compartment within a boat, ship, submarine, or other floating structure that holds water is called a ballast tank. Water should be moved in and out from the ballast tank to balance the ship. In a vessel that travels on the water, the ballast will be kept below the water level, to counteract the effects of weight above the water level. The ballast may be redistributed in the vessel or disposed of altogether to change its effects on the movement of the vessel.
English
Etymology
From Middle English bar (“bare”) + last (“load”).
Pronunciation
- (Received Pronunciation, US) IPA(key): /ˈbæl.əst/
- Rhymes: -æləst
Noun
ballast (usually uncountable, plural ballasts)
- (nautical) Heavy material that is placed in the hold of a ship (or in the gondola of a balloon), to provide stability.
- (figurative) Anything that steadies emotion or the mind.
- Coarse
