Wax has traditionally referred to a substance that is secreted by bees (beeswax) and used by them in constructing their honeycombs. It is an imprecisely defined term generally understood to be a substance with properties similar to beeswax, namely · plastic (malleable) at normal ambient temperatures · a melting point above approximately 45 °C (113 °F) (which differentiates waxes from fats and oils) · a relatively low viscosity when melted (unlike many plastics) · insoluble in water · hydrophobic Waxes may be natural or artificial. In addition to beeswax, carnauba (a plant epicuticular wax) and paraffin (a petroleum wax) are commonly encountered waxes which occur naturally. Earwax is an oily substance found in the human ear. Some artificial materials that exhibit similar properties are also described as wax or waxy.