Absolute: A concentrated semi-solid aromatic material, usually obtained by alcohol extraction.
Aromatic: A substance with a strong aroma or smell.
Attar: Attars are essential oils that have been distilled using a unique process into a base of sandalwood oil. The sandalwood acts as a fixative and enhances the floral notes.
Bath Base: In aromatherapy, a non-alcoholic agent that is used to distribute or dissolve essential oils evenly onto the surface of the bathwater. See also
Carrier: Often a vegetable oil, but it can be a base cream, lotion, gel or shampoo etc which is used to dilute pure essential oils for application.
Chemotype: Plants of the same genus which appear externally identical but have a variation in the chemical constituents, often due to climatic, altitude or soil conditions.
Chemovar: This is an abbreviation for 'chemotype variety' and is usually applied to the description of the plant, rather than the extracted oil.
Cold Pressed: A natural physical process used to extract vegetable oils, and also essential oils from citrus fruits. Vegetable oils extracted in this way retain their essential fatty acid content since no heat or chemicals are used in the process.
Compress: A folded piece of material or lint applied hot or cold to the body.
Concrete: A waxy semi-solid or solid material derived from plant material by a solvent.
Cultivar: A variety of plant which has been developed as a result of cultivation, usually by means of hybridization.
Dispersant: In aromatherapy; a non-alcoholic agent or surfactant that is used to distribute or dissolve essential oils evenly into the surface of water.
Essential Oil: The essence extracted from flowers, plants, herbs, leaves, fruits, woods and gums by steam distillation or other methods of extraction.
Fixed Oil: A vegetable oil, non-volatile.
Genus: A category (in botany) ranking below a family and above a species which usually contains a group of species with similar characteristics.
Gum: Any of various viscous substances exuded by plants and trees that dries on exposure to air into water-soluble, non-crystalline, brittle solids.
Heartwood: The central portion of a tree trunk.
Hydrolat: See Hydrosol.
Hydrosol: True hydrosols are produced by water or steam distillation of the flower or herb, and contain most of the hydrophilic (water soluble) molecules from the plant or flower material that did not distil into the essential oil. Also known as hydrolat, hydrolate, distillate water or floral water.
Infusion: (See macerate and phytol) Prepared by steeping the plant material in water or base oil.
Limbic System: A group of brain structures that is responsible for our feelings, emotions, motivations and influences the endocrine and autonomic motor systems. It also plays an important part in learning and memory. This system includes the thalamus, hypothalamus, amygdala, and prefrontal cortex.
