Patchouli oil is an essential oil that comes from the leaves of the patchouli plant. It's often used for things such as skin conditions, relieving stress, or controlling appetite. You can apply the diluted oil to your skin or use it for aromatherapy. most often associated with the woody fragrance family because of its robust, earthy character, but it's used to create stunning oriental, fougre, and chypre fragrances as well. As a standalone note, most would agree that patchouli mainly smells earthy and musky.