any heavy material used to stabilize a ship or airship
"The captain ordered water pumped into the lower tanks to add ballast and keep the boat steady in the rough waves."
coarse gravel laid to form a bed for streets and railroads
"The construction crew spread several inches of ballast across the railroad tracks before laying the new ties."
an attribute that tends to give stability in character and morals; something that steadies the mind or feelings
"After years of drifting through aimless parties, reading philosophy became his ballast against the chaos of modern life."
a resistor inserted into a circuit to compensate for changes (as those arising from temperature fluctuations)
"The engineer installed a precision ballast in the LED driver to stabilize output despite the sudden drop in ambient temperature."
an electrical device for starting and regulating fluorescent and discharge lamps
"The electrician installed a new ballast to fix the flickering lights in the office."
Heavy material that is placed in the hold of a ship (or in the gondola of a balloon), to provide stability.
"The captain ordered sand pumped into the hold as ballast to keep the vessel stable during the storm."
make steady with a ballast
"The captain ordered water into the tanks to add ballast and keep the ship steady during the rough storm."
To stabilize or load a ship with ballast.
"The captain ordered fresh water to be pumped into the tanks to add ballast and keep the vessel stable in the rough waves."