1. A white crystalline substance, C6H4(OH)2, obtained by the reduction of quinone. It is a diacid phenol, resembling, and metameric with, pyrocatechin and resorcin
   - hydroquinone

Derived forms: quinols

• xxxiv
• xxxv
• xxxvi
• xxxvii
• xxxviii
• XXY
• XXY-syndrome
• XY
• xylan
• Xylaria
• Xylaria mali
• Xylaria polymorpha
• Xylariaceae
• xylem
• rydberg
• rydberg constant
• rydberg unit
• Rydberg's penstemon
• rye
• rye bread
• rye ergot
• rye whiskey
• rye whisky
• ryegrass
• Rynchopidae