1. (n.) A kind of knot often used at the end of a rope; a wall knot; a wale.

2. (n.) A work or structure of stone, brick, or other materials, raised to some height, and intended for defense or security, solid and permanent inclosing fence, as around a field, a park, a town, etc., also, one of the upright inclosing parts of a building or a room.

3. (n.) A defense; a rampart; a means of protection; in the plural, fortifications, in general; works for defense.

4. (n.) An inclosing part of a receptacle or vessel; as, the walls of a steam-engine cylinder.

5. (n.) The side of a level or drift.

6. (n.) The country rock bounding a vein laterally.

7. (v. t.) To enclose with a wall, or as with a wall.

8. (v. t.) To defend by walls, or as if by walls; to fortify.

9. (v. t.) To close or fill with a wall, as a doorway.

arch dam arm armor armor-plate backstop balustrade bamboo curtain bank bar barbed wire barrage barricade barrier battle bear-trap dam beaver dam block blockade bluff boom boundary brattice breakwater breastwork brick wall buffer buffer state bulkhead bulkhead in bulwark bumper cage castellate cliff cloison close in cofferdam collision mat contravallation coop corral crag crenellate cushion dam defense diaphragm dig in dike dissepiment ditch divide dividing line dividing wall division earthwork embankment embattle entrench envelop escarpment face fence fence off fences fender fortify garrison gate gravity dam groin hedge hedgerow hem hoarding hydraulic-fill dam immure interseptum iron curtain jam jetty leaping weir levee logjam man man the garrison mat midriff midsection milldam mine moat mole mound pad pale paling palisade palisades panel parapet paries partition party wall picket portcullis precipice property line rail railing rampart retaining wall roadblock rock-fill dam scar scarp seawall separate separation septulum septum set apart shock pad shutter dam steep stockade stone wall stop trellis vallation vallum wall off weir wicket dam work zigzag fence