potassium-argon dating: Meaning and Definition of

po•tas'si•um-ar'gon dat"ing

Pronunciation: (pu-tas'ē-um-är"gon), [key]
— Geol. Geol.
  1. a method for estimating the age of a mineral or rock, based on measurement of the rate of decay of radioactive potassium into argon.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.