a support or supporter; a stay; a prop. If a be to climb trees that are of any great height, there would be stays and appuies set to it. (Holland) point d'appui . [F, a point of support.
a given point or body, upon which troops are formed, or by which are marched in line or column. An advantageous defensive support, as a castle, morass, wood, declivity, etc.
Origin: f, fr. L. Ad _ podium foothold, gr, dim. Of, foot.