Synonyms and related words :
abruptness, alacrity, expeditiousness, feverishness, furiousness, haste, hastiness, hurriedness, impatience, impetuosity, impetuousness, impulsiveness, overhastiness, precipitance, precipitancy, precipitateness, precipitation, precipitousness, promptness, quickness, recklessness, speed, suddenness, swiftness