heptylene

from The Century Dictionary.

• noun A hydrocarbon (C₇H₁₄), homologous and polymeric with ethylene, existing in three isomeric forms.

from the GNU version of the Collaborative International Dictionary of English.

• noun (Chem.) A colorless liquid hydrocarbon, C7H14, of the ethylene series; also, any one of its isomers. Called also heptene.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun organic chemistry A colourless liquid hydrocarbon, C7H14, of the ethylene series, or any of its isomers.