If I remember correctly, the FDA defines honey as being produced by honeybees from the secretions of plants, so legally I guess so. I personally wouldn't consider honey dew honey adulterated though, as that term to me implies something was added to the honey through artificial means. With honey dew, bees are still collecting a sugary substance out in nature and processing it into honey, it just happened to come from an insect instead of a plant. In my mind that is different from bees visiting a sugar water feeder or getting into snow cone syrup, but maybe that is just me.