- The definition of a hydroxide ion is a negatively charged particle of hydroxide.
An example of hydroxide ion is OH-.
hydroxide ion definition by Webster's New World
Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio. Used by arrangement with John Wiley & Sons, Inc.
the negatively charged ion OH of any base in a water solution
hydroxide ion definition by American Heritage Dictionary
The ion OH-, characteristic of basic hydroxides. Also called hydroxyl ion.