pro·pyl·ene (prō'pə-lēn')
n.
A flammable gas, CH₃CH:CH₂, derived from petroleum hydrocarbon cracking and used in organic synthesis. Also called propene.

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The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2007, 2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved.

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