What does "dome" mean?

Dome: (Arch.) A cupola formed on a large scale. Note: "The Italians apply the term il duomo to the principal church of a city, and the Germans call every cathedral church Dom; and it is supposed that the word in its present English sense has crept into use from the circumstance of such buildings being frequently surmounted by a cupola." Am. Cyc.

Additional senses

  1. 2.Any erection resembling the dome or cupola of a building; as the upper part of a furnace, the vertical steam chamber on the top of a boiler, etc.
  2. 3.(Crystallog.) A prism formed by planes parallel to a lateral axis which meet above in a horizontal edge, like the roof of a house; also, one of the planes of such a form. Note: If the plane is parallel to the longer diagonal (macrodiagonal) of the prism, it is called a macrodome; if parallel to the shorter (brachydiagonal), it is a brachydome; if parallel to the inclined diagonal in a monoclinic crystal, it is called a clinodome; if parallel to the orthodiagonal axis, an orthodome. Dana.
  3. 4.Decision; judgment; opinion; a court decision. [Obs.] Chaucer.

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