arcature

from The Century Dictionary.

• noun In architecture: An arcade of small dimensions, such as a balustrade, formed by a series of little arches.
• noun A blind arcade, used rather to decorate a wall-space, as beneath a row of windows or a cornice, than to meet a necessity of construction.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun a small, arched passageway