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

• ripping bar
• ripping chisel
• ripple
• ripple effect
• ripple mark
• ripple-grass
• rippled
• rippling
• ripply
• riprap
• ripsaw
• ripsnorter
• riptide
• RIRA
• RISC
• rise
• rise to power
• rise up
• risen
• riser
• riser main
• riser pipe
• riser pipeline
• rishi
• risibility