Risk aversion is traditionally defined in the context of lotteries over monetary payoffs. This paper extends the notion of risk aversion to a more general setup where outcomes (consequences) may not be measurable in monetary terms and people may have fuzzy preferences over lotteries, i.e. they may choose in a probabilistic manner. The paper considers comparative risk aversion within neoclassical expected utility theory, a constant error/tremble model and a strong utility model of probabilistic choice (which includes the Fechner model and the Luce choice model as special cases). The paper also provides a new definition of relative riskiness of lotteries.