The Soli Essentials Aromatherapy Glossary is a concise compendium of terms to help demystify commonly used terms in the field of aromatherapy.
AbsoluteProducts obtained from a concrete, a pomade or a resinoid by extraction with ethanol or hexane at room temperature. Used predominantly by perfumers.
AdulterantSubstances such as essential oils, natural aromatic compounds or synthetic aroma-chemicals added to an essential oil.
Aroma ProfileA description of an essential oil’s fragrance in terms of the various odor notes that contribute to its smell.
Base NoteThe base note describes the deeper, richer aspect of a perfume, essential oil, or essential oil blend. It accounts for the last impression of a fragrance and consists of components that evaporate slowly. Also known as the dryout (the lingering smell of an oil after the top and middle notes have evaporated), it is characteristic of earthy, rooty and balsamic fragrance notes.
C02 ExtractionIs a method of extraction involving the use of carbon dioxide compressed under high pressure at relatively low temperatures. CO2 extracts are more similar to the taste and the aroma of a fresh plant as opposed to essential oils.
Carrier OilFatty or fixed oils of vegetable origin used to dilute essential oils and deliver them to the body, primarily onto the skin, where they also serve as a lubricant for transdermal application.
Chemical constituentsUnique chemical compounds that make up an essential oil. An essential oil can have tens to hundreds of chemical constituents.
CompressA warm or cool cloth that is damp and saturated with an essential oil then placed over an area of the body.
Contraindication A consideration in which the condition of an individual (for example, whether they are pregnant or have a skin ailment) prevents the use of specific essential oils due to the possible negative effect of one or more of its chemical constituents.
Diffuser (electric) Unlike passive diffusers, these devices vaporize undiluted essential oils for example via ultrasonic vibration.
Diluted Opposed to neat application of essential oils to the skin, diluted essential oils are mixed with carrier oils at various percentages according to an application, condition, and/or safety consideration.
EmulsifierA substance that dissolves in both water and oil. Because essential oils are hydrophobic and insoluble in water, an emulsifier is needed when mixing them with water.
EnergeticThe overall effect of a natural substance such as an essential oil on the mind, body and spirit of an individual; its influence on their vital energy (Qi in Chinese medicine; Prana in Ayurveda).
EnfleurageAprocess whereby fragrant materials are infused into solid, odorless fats. Traditional cold enfleurage used refined lard or tallow spread on a frame; the petals were placed on top of the fat. Warm or hot enfleurage involved first heating the fat, adding petals, draining the fat, and repeating with more petals.
Essential OilA volatile liquid extracted from the fresh or dried plant material of a single aromatic plant species through distillation or mechanical expression.
ExpressionA mechanical method of essential oil extraction where volatile constituents are pressed, squeezed or compressed from the peels of citrus fruits.
ExtenderNon-odorous adulterants such as mineral oil and ethanol added to essential and carrier oils.
Furanocoumarin Free (FCF)When photosensitizing furanocoumarins are removed by fractional distillation. An example is bergamot FCF essential oil.
GCMS ReportAlso known as a chromatogram, shows the purity of an essential oil through quantifying percentages of each chemical constituent.
HydrodistillationA type of distillation involving the extraction of aromatic compounds from plants in which the plant material is first soaked in water, before being vaporized, condensed and separated.
Hydrophobic A liquid substance that does not dissolve in water.
HydrosolA water byproduct or main product of an essential oil distillation. Also referred to as aromatic water, floral water and hydrolat.
MacerationPlant material that is broken down and added to a carrier oil which acts as a solvent.
Middle NoteAlso known as the heart note, the middle note describes the main body of a perfume, essential oil, or essential oil blend. It accounts for the second impression of a fragrance and consists of components that evaporate at a moderate rate. It is characteristic of floral and fruity fragrance notes.
Nasal Inhaler A small, hand-held plastic device containing a fibrous cartridge into which undiluted essential oils can be added for nasal inhalation.
NeatAlso known as undiluted. Neat application is applying essential oils to the skin without being added to a carrier oil.
Nebulizar An electrical device that diffuses undiluted essential oils through the use of a fine stream of air in order to produce a spray or mist.
NoteThe individual odor components of a perfume or natural fragrance, described in terms of their character (floral, herbaceous, etc) and their relative lightness or heaviness (top, middle, base notes).
OxidationA process of chemical reaction that degrades and can reduce the efficacy and safety of essential oils over time. This process can be accelerated by exposure to heat, sunlight, and air.
Passive DiffuserSurfaces that allow for the natural aerial diffusion of essential oils, such as lava rock, handkerchiefs, rocks, and clay.
PerfumeA blend of absolutes, essential oils, aromatic compounds, fixatives, and solvents.
PharmacokineticsThe study of how essential oils are absorbed, metabolized and excreted by the human body.
Phototoxicity or PhotosensitizationA reaction to sunlight or tanning beds induced by certain chemical constituents (e.g. furanocoumarins such as bergapten, psoralen and angelicin) when applied to the skin.
PurityCan be measured with known parameters such as no synthetics, no diluents, and no contaminations.
ResinSubstances produced by plants for their defense. Some are aromatic such as the oleo-resin frankincense, and the gum-resin myrrh.
Scent Flight A collection of oils that are selected from the Soli Signature Series that allows you to experience a range of scent. Soli offers three varieties of lavender, three varieties of frankincense and a range from the Amazon region.
Shelf lifeThe suggested length of time an essential or carrier oil can be safely used if stored properly.
Sitz BathA bath prepared with warm water, usually epsom salts and a few drops of essential oil. Usually only part of the body is immersed in the bath.
Solubility The ability of a substance to dissolve in a liquid. For example, an essential oil is soluble in a fixed carrier oil but insoluble in water.
SolventDissolves substances. Examples are hexane and ethanol.
Solvent EtractionThe extraction of the aromatic compounds from plants through the use of chemical solvents such hexane and ethanol to produce concretes, absolutes, and resinoids.
Spot ApplicationThere are some scenarios where undiluted essential oils may be used - for example in the case of insect bites, centralized infections, or where benefits outweigh the risk; however, this practice should only be carried out professionally trained clinical aromatherapists. Using undiluted essential oils can increase the risk of skin reactions, systemic toxicity, and drug interactions.
Steam BathAdd 1-2 drops to a bowl of hot water. Cover head and bowl with towel and deeply inhale steam. Intermittent inhalation: 3-5 minutes on and then 2 minutes off. No more than 25 minutes of inhalation per session. A minimum of 1 hour between sessions.
Steam distillationOne of several types of distillation involving the extraction of temperature-sensitive substances such as aromatic compounds from plants through their vaporisation by steam followed by their condensation and separation.
SubcriticalExtraction involving carbon dioxide of only the aromatic compounds
SupercriticalExtraction involving carbon dioxide of the aromatic compounds as well as non-volatile molecules
SyntheticA chemically-created substance which mimics a natural substance.
Top NoteAlso known as the head note, the top note describes the lighter, fresher aspect of a perfume, essential oil, or essential oil blend. It accounts for the first impression of a fragrance and consists of components that evaporate relatively quickly. It is characteristic of citrus and camphoraceous fragrance notes.
Ultrasonic DiffuserWater and ultrasonic vibration used in combination to disperse undiluted essential oils.
Viscosity A measurement of the thickness or thinness of a liquid substance. For example, a vegetable oil is more viscous than water.
Volatile Readily evaporating at normal temperatures.
Wild HarvestedThe gathering of aromatic medicinal plants from their natural habitats.