See whimsical in Webster's New World Roget's A-Z Thesaurus II
adjective
Determined or marked by whim or caprice rather than reason:
arbitrary, capricious. See surpriseFollowing no predictable pattern:
capricious, changeable, erratic, fantastic, fantastical, fickle, freakish, inconsistent, inconstant, mercurial, temperamental, ticklish, uncertain, unpredictable, unstable, unsteady, variable, volatile. See change, continueAppealing to fancy:
fanciful, fancy, fantastic, fantastical, imaginative. See plain
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