n.速度，迅速,
Merriam-Webster Online Dictionary
velocity (noun)1.
a) quickness of motion - speed the velocity of sound
b) rapidity of movement - [my horse's] strong suit is grace & personal comeliness, rather than velocity Mark Twain
c) speed imparted to something - the power pitcher relies on velocity Tony Scherman
2.
the rate of change of position along a straight line with respect to time the derivative of position with respect to time
3.
a) rate of occurrence or action - rapidity the velocity of historical change R. J. Lifton
b) rate of turnover - the velocity of money
Merriam-Webster Online Thesaurus
velocity (noun)a high rate of movement or performance
SYNONYMS:
celerity, fastness, fleetness, haste, hurry, quickness, rapidity, rapidness, speediness, swiftness, velocityRELATED WORDS:
clip, gait, pace, rate, tempo; drive, hustle; acceleration, hastiness, precipitation, precipitousness, rush; alacrity, dispatch, expedition, expeditiousness, promptitude, promptness; warp speedNEAR ANTONYMS:
languidness, languor, leisureliness, lethargy, torpidity, torpor; reluctance; deliberateness, deliberation; dilatoriness, lateness, pokiness, procrastination