[], (Noun)

Definitions:
- Each of a number of isomeric liquid alkenes with the formula C₅ H₁₀; especially either of the straight-chain isomers CH₂ =CH(CH₂)₂ CH₃ ("1-pentene") or CH₃ CH=CH(CH₂)CH₃ ("2-pentene"). Compare "amylene", pentylene.


Phrases:

Origin:
late 19th century; earliest use found in Philosophical Transactions of the Royal Society of London. From penta- + -ene