vinyl

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. The univalent chemical radical CH₂CH, derived from ethylene.
2. n. Any of various compounds containing the vinyl radical, typically highly reactive, easily polymerized, and used as basic materials for plastics.
3. n. Any of various typically tough, flexible, shiny plastics, often used for coverings and clothing.
4. n. Phonograph records considered as a group: a secondhand store that buys and sells vinyl.
5. idiom. on vinyl In the medium of phonograph recordings: an old song available only on vinyl.

Century Dictionary and Cyclopedia

1. n. The compound univalent radical CH₂CH, which appears characteristic of many ethylene derivatives.

Wiktionary

1. n. chemistry, uncountable The univalent radical CH2=CH−, derived from ethylene
2. n. countable Any of various compounds and substances containing the vinyl radical, especially various tough, flexible, shiny plastics
3. n. collectively, uncountable Phonograph records as a medium
4. adj. chemistry containing the vinyl radical
5. adj. Made of polyvinyl chloride.

GNU Webster's 1913

1. n. (Chem.) The hypothetical radical C2H3, regarded as the characteristic residue of ethylene and that related series of unsaturated hydrocarbons with which the allyl compounds are homologous.

WordNet 3.0

1. n. shiny and tough and flexible plastic; used especially for floor coverings
2. n. a univalent chemical radical derived from ethylene