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Related to fatty oil: fixed oil
1. an unctuous, combustible substance that is liquid, or easily liquefiable, on warming, and is not miscible with water, but is soluble in ether. Such substances, depending on their origin, are classified as animal, mineral, or vegetable oils. Depending on their behavior on heating, they are classified as volatile or fixed. For specific oils, see under the name, as castor oil.
2. a fat that is liquid at room temperature.
essential oil volatile o.
expressed oil (fatty oil) (fixed oil) one that is not volatile, i.e., does not evaporate on warming; such oils consist of a mixture of fatty acids and their esters, and are classified as solid, semisolid, and liquid, or as drying, semidrying, and nondrying as a function of their tendency to solidify on exposure to air.
volatile oil an oil that evaporates readily; such oils occur in aromatic plants, to which they give odor and other characteristics.
an oil derived from both animals and plants; chemically, a glyceride of a fatty acid that, by substitution of the glycerine by an alkaline base, is converted into a soap; a fatty oil, in contrast to a volatile oil, is permanent, leaving a stain on an absorbent surface, and thus is not capable of distillation; it is obtained by expression or extraction; the consistency varies with the temperature, some being liquid (o.'s proper), others semisolid (fats), and others solid (tallows) at ordinary temperatures; both liquid and semisolid oils are congealed by cold and the solids are liquified by heat.
Synonym(s): fixed oil
fat·ty oil(fat'ē oyl)
An oil derived from both animals and plants; chemically, a glyceride of a fatty acid that is converted into a soap by substitution of the glycerine with an alkaline base; a fatty oil, in contrast to a volatile oil, is permanent and not capable of distillation.