Synonyms and related words :
abruptness, alacrity, capriciousness, desultoriness, deviability, eccentricity, erraticism, expeditiousness, feverishness, fickleness, flightiness, forwardness, freakishness, furiousness, haste, hastiness, hurriedness, impatience, impetuosity, impetuousness, impulse, inconsistency, inconstancy, instability, irregularity, mercuriality, moodiness, overhastiness, precipitance, precipitancy, precipitateness, precipitation, precipitousness, precociousness, precocity, prematureness, prematurity, promptness, quickness, rashness, recklessness, restlessness, rush, shiftiness, speed, suddenness, swiftness, uncertainty, undependability, unfixedness, uninhibitedness, unpredictability, unreliability, unrestraint, unsettledness, unstableness, unsteadfastness, unsteadiness, untimeliness, variability, variation, variety, wantonness, waywardness, whimsicality