[], (Noun)

Definitions:
- Each of two unsaturated, heterocyclic compounds having the formula C₅ H₆ O, whose molecules have a six-membered ring consisting of five carbon atoms and one oxygen atom with two double bonds between carbon atoms; specifically γ-pyran. Also: a substituted derivative of such a compound; any compound containing a pyran ring.


Phrases:

Origin:
early 20th century; earliest use found in Journal of the Chemical Society. From pyr- + -an