For those who are too afraid to ask, hydrosol is a water-based byproduct of the essential oil distillation process. In other words, when you make essential oils, you steam raw plant material, condense it into liquid in a cold chamber, which then produces essential oil, and a beautiful hydrosol. Hydrosols have a variety of uses, some of which being, body spray, linen spray, room spray, facial toner, ingredient for lotions and creams, and carry a variety of medicinal properties dependent on the plant.