- Also called ballast resistor. 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.
- 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)
Origin of ballast
Examples from the Web for ballast
But are the ballast masses, so critical for the Apollo entry guidance to work properly, really gone as they should be?Curiosity’s Mars Landing Narrated Moment by Moment by Flight Director Keith Comeaux|Keith Comeaux|August 7, 2012|DAILY BEAST
It had no other ballast than himself, his wife and children, and the Christmas fare.The Visionary|Jonas Lie
After passing a week at Gibraltar, to take in some dollars, we sailed for New Orleans, in ballast.Ned Myers|James Fenimore Cooper
They got into the car, and the bags of ballast were tossed overboard.Frank Merriwell's Bravery|Burt L. Standish
The prisoners were handcuffed, or chained together, and placed in the hold, on the ballast.On the Spanish Main|John Masefield
Poverty and responsibility had given him ballast, and love for his own little brood had softened his heart and vitalized his soul.Little Journeys To The Homes Of Great Teachers|Elbert Hubbard
British Dictionary definitions for ballast
Word Origin for ballast
Word Origin and History for ballast
"heavy material used to steady a ship," 1520s, from Middle English bar "bare" (see bare; in this case "mere") + last "a load, burden," or borrowed from identical terms in North Sea Germanic and Scandinavian (cf. Old Danish barlast, 14c.). "Mere" because not carried for commercial purposes. Dutch balg-last "ballast," literally "belly-load," is a folk-etymology corruption.