appui, n. [F., fr. L. ad + podium foothold, Gr. , dim. of , , foot.].
Point d'appui (/)
. [F., a point of support.] (Mil.) (a) A given point or body, upon which troops are formed, or by which are marched in line or column. (b) An advantageous defensive support, as a castle, morass, wood, declivity, etc. (c) any point of support or basis of operations, as a rallying point.