Splayed opening

In architecture, a splayed opening is a wall opening that is narrower on one side of the wall and wider on another. When used for a splayed window, it allows more light to enter the room. In fortifications, a splayed opening is used to broaden the arc of fire.

Splayed arch

A splayed arch is an arch where the springings are not parallel, causing an opening on the exterior side of an arch to be different than the interior one. The intrados of a splayed arch is not generally cylindrical as it is for typical arch, but has a conical shape.
José Calvo-López, a Spanish scholar of architecture, subdivides the splayed arches into symmetrical, and the ox horn arches, where one springer is orthogonal to the wall, and another is not, creating a "warped" intrados.

Double-splayed window

Double-splayed windows, widening towards both wall faces, with the narrowest part in the middle of a wall, are common in the Anglo-Saxon architecture, although the use of this trait for dating is questionable, and English church buildings of the 12th century have such windows too.

Portals

Widely splayed portals were used in the Gothic architecture to display sculpture on the western facades of churches.