Which of the following best defines a rotunda?

• A. A circular building often covered by a dome.
• B. An ornamental late Baroque style with excess decoration.
• C. A facing of impact-resistant material that protects a structure.
• D. A circular stained-glass window with decorative motifs.

Answer: (A)

Rotunda refers to a round, usually circular building or interior space that is often topped by a dome. The idea centers on the shape and the architectural form—the circular plan and often a domed roof create a spacious, centralized room that can serve as a grand ceremonial or public area. The term comes from Latin rotundus meaning round, and you can see it in famous examples like the Pantheon or grand capitol spaces where the circle and dome define the experience.

The other descriptions point to different features: a decorative Baroque style speaks to surface ornament, not the building's shape; a protective facing describes defensive cladding rather than a form; a circular stained-glass window is a type of window, not a volumetric space. So the best definition is a circular building often covered by a dome.