capstone Meaning, Definition & Usage

  1. noun a final touch; a crowning achievement; a culmination
    finishing touch; copestone.
  2. noun a stone that forms the top of wall or building
    coping stone; copestone; stretcher.

WordNet


Cap"stone` noun
Definitions
  1. (Paleon.) A fossil echinus of the genus Cannulus; -- so called from its supposed resemblance to a cap.

Webster 1913