1. A term coined by Nassim Taleb to represent things that benefit from disorder. 2. The opposite of fragile. 3. When you have more to gain than lose in the presence of uncertainty (positive asymmetric payoff). 4. According to Taleb, antifragile things have a convex response to a stressor or source of harm (for some range of variation), leading to a positive sensitivity to increase in volatility (or variability, stress, dispersion of outcomes, or uncertainty). Contrast with fragile, robust.
Read a blog post entitled: Agile & Risk Management: Antifragile