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