caprice

1 a sudden impulsive and apparently unmotivated idea or action an out-of-character caprice led him to take the day off from work and go to the beach Synonyms bee, whim, crank, fancy, freak, humor, kink, maggot, megrim, notion, vagary, vagrancy, whimsy (also whimsey)Related Words capriciousness, fancifulness, fantasy (also phantasy), freakishness, impetuosity, whimsicality; conceit; concept, conception, image, impression, mind's eye, picture, thought; brainstorm, inspiration

2 an inclination to sudden illogical changes of mind, ideas, or actions his knack for picking racetrack winners appears to owe as much to caprice as it does to a canny assessment of horseflesh Synonyms whimsicality, capriciousness, freakishness, impulsiveness, whimsicalnessRelated Words mercurialness, moodiness, unpredictability, willfulness; eccentricity, flakiness; arbitrariness, fickleness, inconstancy, irregularity, volatileness, volatility; changeability, flexibility, mutability, variability, variablenessNear Antonyms levelheadedness, practicality, reasonability, reasonableness; fastness, firmness, fixedness, immovability, immovableness, immutability, inflexibility, invariability; changelessness, constancy, stability, steadfastness, steadiness