Raw honey is raw, unpasteurized honey that hasn't been heated over 60°C. And raw doesn't just mean raw in temperature, it also means raw by activity - raw honey has the enzymes of the bee's body still intact, which are necessary for flora-friendly digestion.
Raw can also be distinguished from pasteurized or filtered honey by its appearance: raw honey tends to separate into layers of creamed nectar with thousands of tiny bubbles throughout. This happens because raw honey contains small amounts of bee pollen grains and wax particles that can serve as food for naturally occurring yeasts (which help to naturally ferment the sugars). As a result, there may be some natural yeast fermentation taking place within the plastic raw honey jar.
Raw honey does not mean raw in healthfulness: raw commercial honey can, and do, contain residues of pesticides used on the bees and wax.
Raw = unfiltered; unpasteurized; unheated; containing bee enzymes; containing tiny amounts of pollen grains and waxes that ferment into alcohols that may cause tiny yeast-bubble fermentation within the raw honey (but this doesn't necessarily deplete its anti-bacterial or anti-viral properties)