Aromatherapy Glossary

Amrita's glossary of aromatherapy terms and aromatherapy definitions is organized in alphabetical order. Click on any of the links below.

Blending Essential Oils

Blending refers to the science of creating the right combination and proportion of essential oils that will help with a particular emotional or physical condition. Naturally, it's important to create a therapeutic blend that has a pleasing aroma.

When blending, it's important to select oils based not only on their properties and characteristics but also on any contraindications or safety issues that might affect other aspects of your health. For example, Holy Basil blends with Rosemary under normal conditions. However, Rosemary is contraindicated in pregnancy. That's why we always recommend consulting a professional unless you know what you are doing.

Read "How To Blend".

Characteristics of Essential Oils

Refers to the aromatic properties of an essential oil and its effects on the sense of smell.

Common Name and Botanical Name of an Essential Oil

Lavender, Cedar and Eucalyptus are examples of the common names of plants used to create essential oils. However, there are different varieties of each of these plants. To differentiate these varieties, the botanical name (also referred to as the Latin binomial) is used to tell them apart. For example, even though two different oils are referred to as Eucalyptus, they might come from different plants and have different therapeutic properties. Therefore, the botanical name is needed to distinguish between the two plants. In the case of Eucalyptus, two botanical names are Eucalyptus globulus and Eucalyptus radiata.

Country of Origin

This refers to the country in which the essential oil was produced. Amrita makes every effort to obtain each oil from the country where the particular plant will produce the finest essential oil, like Rose Otto from Bulgaria and Bergamot from Italy. At times we offer two versions of the same oil from two different countries, if price and quality warrant it. See where Amrita's essential oils come from. Note: As we sometimes change suppliers, this may not be up to date, but it gives a general idea of where essential oils are grown. This was how it was in 2015.

Extraction Methods

The three main methods of extracting essential oils are:

See What To Look For In Essential Oils for some extra trips regarding  extraction methods.

Extraction via Cold Pressing (Expression)

This refers to obtaining oils through pressing and grinding fruit or seeds with the use of heavy granite millstones or modern stainless steel presses, which are found in large commercial operations. Although pressing and grinding produces heat through friction, the temperature must not rise above 120ºF for any oil to be considered cold-pressed. Cold-pressed oils retain all of the flavor, aroma and nutritional value of the original plant part.

Extraction via Distillation

Steam distillation is the most common method of extracting essential oils. Many old-time distillers favor this method for most oils and say none of the newer methods produce better-quality oils.

Steam distillation is done in a still. Fresh, or sometimes dried, botanical material is placed in the plant chamber of the still. Pressurized steam is generated in a separate chamber and circulated through the plant material. The heat of the steam forces the tiny intercellular pockets that hold the essential oils to open and release the oils. The temperature of the steam must be high enough to open the pouches but not so high that it destroys the plants or fractures or burns the essential oils.

As they are released, the tiny droplets of essential oil evaporate and, together with the steam molecules, travel through a tube into the still's condensation chamber. As the steam cools, it condenses into water. The essential oil forms a film on the surface of the water. To separate the essential oil from the water, the film is then decanted, or skimmed off the top.

The remaining water, a byproduct of distillation, is called floral water, distillate or hydrosol. It retains many of the therapeutic properties of the plant, making it valuable in skin care for facial mists and toners. In certain situations, the floral water may be preferable to the pure essential oil, such as when treating a sensitive individual or a child, or when a more diluted treatment is required.

Extraction with Volatile Solvents

Another method of extraction is solvent extraction, which is used on delicate plants. It yields a higher amount of oil at a lower cost. In this process, a chemical solvent is used to saturate the plant material and pull out the aromatic compounds. This renders a substance called a concrete. The concrete can then be dissolved in alcohol to remove the solvent. When the alcohol evaporates, an absolute remains.

Although more cost-effective than enfleurage (a process of extracting perfumes by exposing odorless oils to the fragrance of fresh flowers), solvent extraction has disadvantages. Residues of the solvent may remain in the absolute and cause side effects. While absolutes or concretes may be fine for fragrances or perfumes, they are not especially desirable for skin care applications. Only oils extracted with alcohol as the solvent should be used for aromatherapy purposes. Those extracted using hexane and other solvents should not be used.

Sometimes the resin from trees such as Benzoin, Frankincense, and Myrrh are extracted using liquid CO2. 

Health Benefits

Based on the properties and characteristics of an oil, information on health benefits gives you more specific knowledge of how an essential oil affects body, mind and spirit.

Perfumery Fragrance Note

This refers to how tenaciously the scent of an essential oil lingers. "Top notes," relative to other notes, usually disappear faster, and "base notes" last the longest. Adding a small amount of a middle note will make a top note last longer. Rounding the blend off with just a single drop or two of a base note anchors it. Normally speaking, the lower notes will dominate a blend if all notes are used in equal amounts.

Plant Part Used in the Extraction Processes

Essential oils come from various parts of plants: seeds, bark, leaves, stems, roots, flowers and fruit. Essential oils carry the fullest therapeutic properties of the plant only when extracted from the appropriate part of the plant.

Properties of Essential Oils

The actions of essential oils on the physiology that are supported by reliable scientific evidence.