Heptane

Hep″tane (?), n. [Gr. επτἅ seven.] (Chem.) Any one of several isometric hydrocarbons, C7H16, of the paraffin series (nine are possible, four are known); — so called because the molecule has seven carbon atoms. Specifically, a colorless liquid, found as a constituent of petroleum, in the tar oil of cannel coal, etc.