accidental adventitious adventurous agnostic aleatory ambiguous capricious casual causeless chance chancy changeable contingent dangerous destinal difficult doubtful doubting equivocal erratic fatal fatidic fickle fluky fortuitous full of risk hairy hazardous hesitant hesitating iffy incalculable incidental indecisive indemonstrable indeterminate irresolute polysemous riskful risky skeptical speculative ticklish touch-and-go tricky unaccountable uncaused uncertain unconfirmable unconvinced undetermined undivinable unexpected unforeseeable unforeseen unlooked-for unpersuaded unpredictable unprovable unsure unverifiable variable venturesome venturous wavering whimsical wildcat