Synonyms and related words :
celerity, dispatch, expedition, fastness, flight, flit, flurry, ground speed, haste, hurry, instantaneousness, knots, lightning speed, miles per hour, precipitation, promptitude, promptness, quickness, rapidity, round pace, rpm, rush, shock wave, snappiness, sonic barrier, sonic boom, sound barrier, speed, speed of sound, speediness, swift rate, swiftness, velocity