Arch. [Fr.] An arched or ‘flying’ buttress, ‘whose object is to counteract the thrust of the main vault of the edifice’ (Gwilt).
1731. in Bailey.
1767. Ducarel, Anglo-Norm. Antiq., 27. The walls of this Church are cased on the outside by thirty-two arc-boutants or buttresses.
1823. Rutter, Fonthill, 9. The ceiling is divided … by a broad arc-boutant in the middle.
