Squalen

Part of speech: noun

Definitions

1. A natural oily hydrocarbon compound found in shark liver oil and certain plant oils, used in cosmetics and as a precursor to steroids
2. An unsaturated organic substance with a long carbon chain, obtained chiefly from shark liver and some vegetable oils, and used in skin care products
3. A naturally occurring oily triterpene hydrocarbon present in shark liver oil and certain plant sources, valued in cosmetics and pharmaceutical chemistry

Etymology: Squalene is named after sharks. The name comes from the Latin "squalus," a word for a kind of shark or sea fish, and the chemical suffix "-ene" marks it as an unsaturated hydrocarbon. Chemist Mikhail Tsvet isolated the compound in 1906 from shark liver oil, but the name was given later, in 1926, by Japanese chemist Tsujimoto Mitsumaru, who had been studying oil from the liver of the Squalus shark. The compound turned out to be far more common than its name suggests. It is a natural part of human skin oil and of many plants, and it is used in vaccine adjuvants and cosmetics. The sharks were simply the first place chemists found it in quantity, so the name records an accident of where the substance was first collected rather than anything it is especially tied to.