Capstone

//ˈkæpˌstoʊn// noun, verb, slang

noun, verb, slang ·Moderate ·High school level

Definitions

Noun
  1. 1
    Any of the stones making up the top layer of a wall; a coping stone.
  2. 2
    a stone that forms the top of wall or building wordnet
  3. 3
    A crowning achievement, culmination or finishing touch. figuratively

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

  4. 4
    a final touch; a crowning achievement; a culmination wordnet
Verb
  1. 1
    To complete as a crowning achievement; to top off. transitive

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

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

Example

More examples

"Extraterrestrials could be seen as gods if their powers dazzle us, but they’d differ from an immanent or transcendent God by being finite, physical beings within the universe, not its root. A hierarchy of beings—us, them, and beyond—fits both religious and speculative frameworks, potentially stretching from the mundane to the near-divine. Whether there’s an ultimate God atop it all, or just an endless progression of "higher" entities, depends on your worldview. What do you think—does the idea of a cosmic pecking order resonate with you, or do you lean toward a singular divine capstone?"

Etymology

From Middle English capston; equivalent to cap + stone.

Related phrases

Data sourced from Wiktionary, WordNet, CMU, and other open linguistic databases. Updated March 2026.