dado

Concise Oxford English Dictionary © 2008 Oxford University Press:
dado /ˈdeɪdəʊ/

▶noun (pl. dados)

• 1 the lower part of the wall of a room, when decorated differently from the upper part.

• 2 N. Amer. a groove cut in the face of a board, into which the edge of another board is fixed.

• 3 Architecture the cube of a pedestal between the base and the cornice.

– origin C17: from Ital., lit. ‘dice or cube’.