capstone

noun

1. Any of the stones making up the top layer of a wall; a coping stone.
2. (figuratively)A crowning achievement, culmination or finishing touch.

   ““You see, I’ve never had a girl friend,” I added, by way of topping the obelisk of silliness with the capstone of fatuity.”

   “Success of the Apollo program has been the capstone to a series of significant accomplishments for the United States in space in a broad spectrum of manned and unmanned exploration missions and in the application of space techniques for the benefit of man.”

verb

1. (transitive)To complete as a crowning achievement; to top off.

   “Capstoning a decade's worth of linked short stories, The Quiet War (2008) was a vivid and tense novel about a solar system sliding into conflict.”

2. (US, informal, transitive)To train in the Capstone Military Leadership Program.

   ““Capstoned” units are now able to train and plan in peacetime with the command with which they will fight in wartime.”