Synonyms for Capricious (same or very similar meaning)
WordNet sense 1 (changeable):
freakish
WordNet sense 2 (not capable of being foretold):
unpredictable
WordNet sense 3 (determined by chance or impulse or whim rather than by necessity or reason):
impulsive, whimsical
WordNet sense 4 (based on or subject to individual discretion or preference or sometimes impulse or caprice):
arbitrary
From the ODE community, based on WordNet
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