a rotunda is a form of:

Rotunda



noun
1.
(1. A circular building, especially one with a dome. 2. a. A large area with a high ceiling, as in a hotel lobby. b. A large round room) អាគាររាងមូលដំបូលក្រឡូម
  • fenestra rotunda
    - ប្រហោងរាងមូលដែលស្ថិតនៅត្រចៀកខាងក្នុង
ENGLISH MEANING
noun
1.
A round building; especially, one that is round both on the outside and inside, like the Pantheon at Rome. Less properly, but very commonly, used for a large round room; as, the rotunda of the Capitol at Washington.