oil (oyl) [Fr. oile fr L. oleum, olive oil, oil]
A greasy liquid not miscible with water, usually obtained from and classified as mineral, vegetable, or animal. According to character, oils are subdivided principally as fixed (fatty) and volatile (essential).
Examples of fixed oils are castor oil, olive oil, and cod liver oil. Examples of volatile oils are oils of mustard, peppermint, and rose.
cade oilJuniper tar.
Liniment containing camphor.
A light, clear oil derived from the pods of an oilseed plant in the rapeseed family. The oil is composed of 7% saturated fat (the lowest saturated fat content of any vegetable oil), 61% monounsaturated fat, and 22% polyunsaturated fat.
The seeds were initially bred and processed in Canada for lower erucic acid levels, making it an edible, nontoxic oil. The commercial oil was changed from the unfortunate rapeseed to Canola oil, from Can(adian) o(il), l(ow) a(cid).
A fixed oil expressed from the seed of the castor-oil plant (Ricinus communis), used externally as an emollient and internally as a cathartic. It is hydrolyzed to ricinoleic acid, which acts as an irritant type of laxative.
chaulmoogra oil, chaulmugra oil, chaulmaugra oil
A vegetable oil used to treat leprosy and some dermatoses. Although generally replaced by sulfones in treatment of leprosy, chaulmoogra oil is still used in areas where leprosy is endemic because of its availability and low cost.
A colorless cooking oil, derived from the nut of the palm tree (Cocos nucifera). It has the highest level of saturated fat (about 91%) of all cooking oils.
cod liver oil
An oil obtained from codfish liver, rich in vitamins A and D.
Cod liver oil was widely used in cases of nutritional deficiency to supply vitamins A and D, esp. for prophylaxis of rickets in infants. It is rarely used now because more efficient and more palatable agents are available.
A fixed oil expressed from the seed of the croton plant (Croton tiglium). It is toxic to skin, heart, muscle, and the gastrointestinal tract.
A volatile oil, esp. one that has an odor and taste, extracted from plants by various means. Some of these oils have been used since antiquity as preservatives and antiseptics, e.g., thymol and eugenol. Some are used in flavorings, perfumes, and medicines. They are usually complex chemicals difficult to purify. Synonym: volatile oil
evening primrose oil
An oil derived from Oenothera biennis, a biennial herb with yellow flowers, that contains omega-6 fatty acids. It is promoted for the treatment of inflammatory conditions, e.g., of the skin or joints.
A popular term for omega-3 fatty acids, which when consumed in the diet in the form of salmon, halibut, and other cold-water fish, reduce the risk of coronary artery disease (CAD). Dietary supplements of fish oil capsules containing omega-3 and/or omega-6 fatty acids, by contrast, have shown inconsistent results in the prevention of CAD.
Any of the oils in plants and animals that are glyceryl esters of fatty acids. These oils serve as food reserves in animals. They are nonvolatile and contain no acid.
Oil extracted from the seeds of the flax plant (Linum usitatissimum
), used as a nutritional supplement. Flaxseed oil contains alpha-linolenic acid, an essential omega-3 fatty acid promoted for its effect in preventing heart disease, inflammatory bowel disease, and arthritis. See: essential fatty acid
; linolenic acid
; omega-3 (?3) fatty acids
halibut liver oil
An oil obtained from the liver of the halibut fish (genus Hippoglossus), rich in vitamins A and D.
An essential oil derived from Lavandula angustifolia, a plant with lavender flowers. The oil is used in aromatherapy to alleviate pain, e.g., during acupressure, massage, and childbirth.
Lorenzo's oil See: Lorenzo's oil
medium-chain triglyceride oil
A cooking oil of medium-chain triglycerides, used therapeutically as a source of calories and fatty acids, esp. in patients with long-chain and very long-chain fatty acid metabolism disorders. These triglycerides are more readily absorbed from the gut than are most long-chain triglycerides.
mineral oilLiquid petrolatum.
An oil obtained by pressing ripe olives (Olea europaea). It is the major fat used in Mediterranean cooking. It has a relatively high content of monounsaturated fatty acids (which reduce levels of low-density lipoprotein cholesterol) and polyphenols (which act as antioxidants). It can be consumed in the diet or used on the skin as an emollient.
A refined oil obtained from the seed kernels of one or more of the cultivated varieties of Arachis hypogaea, used as a solvent for some medicines that are injected intramuscularly.
The oil expressed from the seeds of the safflower plant, Carthamus tinctorius. It is high in linoleic acid and low in saturated fatty acids. Diets rich in safflower oil produce less serum cholesterol and apolipoproteins A-I and B than similar diets in which butter or coconut oil is used as the primary fat source.
Oil obtained from the seeds of Sesamum indicum, used as a pharmaceutical aid and as a cooking oil. Sesame oils occasionally cause contact dermatitis.
silicone oilInjectable silicone.
A commonly used oil obtained from the seeds of the soya plant (soybeans) that is low in unsaturated fat and rich in linolenic acid, an essential fatty acid.
tea tree oil
The aromatic essential oil of Melaleuca alternifolia, used as a topical antibacterial, anti-inflammatory, and antifungal in a range of herbal medicines. Skin irritation may occur in some sensitized people exposed to the oil or if the oil is used in high concentrations.
volatile oilEssential oil.
wheat germ oil
The oil expressed from the germ of the wheat seed. It is a rich source of vitamin E.
wintergreen oil, oil of wintergreen
A colorless, yellowish, or reddish liquid derived from methyl salicylate. It has a characteristic taste and odor and is used as a flavoring substance and as a counterirritant applied topically in the form of salves, lotions, and ointments. See: methyl salicylate