ballastbal‧last /ˈbæləst/ noun [uncountable] 
Word Origin
Word OriginWORD ORIGINballast
ExamplesOrigin:
1500-1600 Probably from Low GermanEXAMPLES FROM THE CORPUS
word sets- I bought nine fluorescent light fixtures-bulbs, ballast, and wire.
- Many nights my bunk was blanketed by blueprints as I worked my way through the schematics of the variable ballast system.
- The flooding followed a 10-15 o list to port, due to water pouring into the forward ballast tanks.
- The reactions and thrust of each deck is taken on elastomeric bearings and by ballast walls.
- They got the ballast out and loaded it into skips and the loco brought it along the line to the plant.
- With ballast weights at each blade tip, the whirling rotor system had tremendous inertia.
- Yet when he spoke of himself, his gaze frequently wandered, as though in search of visual ballast.
WORD SETS► Air
1heavy material that is carried by a ship to make it more steady in the water2material such as sand that is carried in a balloon so that it can be thrown out to make it rise3a layer of broken stones that a road or railway line is built onaerial, adjectiveaero-, prefixaerobatics, nounaerodrome, nounaeronautics, nounairborne, adjectiveaircraft, nounaircrew, nounairfare, nounairfield, nounairline, nounairliner, nounair pocket, nounairport, nounairship, nounairsick, adjectiveairspace, nounairspeed, nounairstrip, nounair terminal, nounair traffic controller, nounairway, nounairworthy, adjectivealtimeter, nounapron, nounautomatic pilot, nounautopilot, nounaviation, nounaviator, nounballast, nounballoon, nounballooning, nounbank, verbbarrage balloon, nounbiplane, nounblack box, nounblimp, nounboarding card, nounboarding pass, nounbulkhead, nounbusiness class, nounbuzz, verbcabin, nouncaptain, nouncarousel, nounceiling, nouncharter flight, nouncheck-in, nounchock, nounchopper, nounchute, nounclub class, nouncontrail, nouncontrol tower, nounco-pilot, nouncowling, nouncraft, nouncrash landing, noundeparture lounge, noundepartures board, noundirigible, noundisembark, verbdive, verbeconomy class, nouneject, verbejector seat, nounfin, nounflap, nounflier, nounflight, nounflight attendant, nounflight deck, nounflight path, nounflight recorder, nounflight simulator, nounfly, verbflyby, nounflyer, nounflying, nounflypast, nounfree fall, nounfuselage, noungate, nounglider, noungliding, noungondola, nounground, verbground control, nounground crew, nounground staff, nounhangar, nounhang-glider, nounhang-gliding, nounhelicopter, nounhelicopter pad, nounheliport, nounhijacking, nounholding pattern, nounhot-air balloon, nounhydroplane, nouninbound, adjectivein-flight, adjectiveinstrument panel, nounjet, nounjet engine, nounjet-propelled, adjectivejet propulsion, nounjoystick, nounjumbo jet, nounjump jet, nounland, verblanding gear, nounlanding strip, nounlayover, nounlift, nounlight aircraft, nounlounge, nounlow-flying, adjectivemicrolight, nounmonoplane, nounnavigation, nounno-fly zone, nounnose, nounnosedive, nounnosedive, verboverfly, verbparachute, nounparachute, verbparachutist, nounpilot, nounpilot, verbpitch, nounpitch, verbplane, nounplot, verbpod, nounpressurized, adjectiveprop, nounpropeller, nounradio beacon, nounrefuel, verbripcord, nounroll, verbroll, nounrotor, nounrudder, nounrunway, nounseaplane, nounseat belt, nounshort-haul, adjectiveski plane, nounskycap, nounsonic boom, nounspoiler, nounsteward, nounstewardess, nounstrut, nounswept-back, adjectiveswoop, verbtail, nountailspin, nountake-off, nountaxi, verbterminal, nountest pilot, nounthrust, nountouchdown, nountransit lounge, nountransport plane, nounturbojet, nounturboprop, nountwin-engined, adjectiveundercarriage, nounupgrade, verbvapour trail, nounwheel, verbwindsock, nounwind tunnel, nounwing, nounwingspan, nounwingtip, nounzeppelin, noun