Skip to main content
Dictionary
Store
Blog
World
Help
Advertise
Chat
System Status
Information Collection Notice
Trademark Concerns
reCAPTCHA Privacy
Terms of Service
reCAPTCHA Terms
Privacy Policy
Accessibility
Report a Bug
Data Request
Contact Us
Security
DMCA
© 1999–2026 Urban Dictionary ®
Mugs
Tees
Hoodies
Pro Customization
Create unique products with your own words and definitions
Preview
Personalize Your Design
Your Word
Your Definition
a tetrapyrrole similar to heme but with a reduced ring and a long phytol chain esterified on to a carboxylic acid side chain. Falls into the class of organic chemicals called polyenes, which have alternating networks of single and double bonds.
Text fits
Save
Cancel