A rectangular building or block of buildings; a building containing a square or rectangular courtyard. †Also occasionally as a mass noun (obsolete).

A round building or space; (the name of) a particular building of this shape. Cf. rotunda, n. Now rare.

A circular building, room, or space. Cf. rotunda, n.

An arched or vaulted roof, chamber, or building. Also more generally: any room or chamber.

A building which is circular both inside and out, esp. one with a dome. Cf. rotundo, n. 1.

A circular domed building or structure; a dome, cupola; a lantern.

A structure resembling in shape an outspread umbrella, or serving for protection against something.

(The name of) an octagonal building in Liverpool, used as a place of worship by a dissenting sect in the late 18th cent. rare.

a tall, narrow circular stone tower with a conical roof, found in Ireland (and also in western Scotland and the Isle of Man) from the 9th cent…

A cone-shaped building enclosing a glass-furnace, tile-kiln, or the like.

attributive and in other combinations esp. applied to a building, from its triangular shape.

A square fort; a quadrangular building or block of buildings. Cf. quadrangle, n. 3.

A colonnaded building, frequently of circular form, surmounted by a dome.

a building or structure with four gates.

In extended use. Any small dome-shaped building or construction.

figurative. A building or part of a building resembling a shoebox. Also attributive.