Merriam-Webster Collegiate Dictionary - wall

 I. noun  Etymology: Middle English, from Old English weall; akin to Middle High German ~; both from Latin vallum rampart, from vallus stake, palisade; perhaps akin to Old Norse volr staff — more at wale  Date: before 12th century  1.  a. a high thick masonry structure forming a long rampart or an enclosure chiefly for defense — often used in plural  b. a masonry fence around a garden, park, or estate  c. a structure that serves to hold back pressure (as of water or sliding earth)  2. one of the sides of a room or building connecting floor and ceiling or foundation and roof  3. the side of a footpath next to buildings  4. an extreme or desperate position or a state of defeat, failure, or ruin the surrounded troops had their backs against the ~ small companies driven to the ~  5. a material layer enclosing space the ~ of a container heart ~s  6. something resembling a ~ (as in appearance, function, or effect); especially something that acts as a barrier or defense a ~ of reserve tariff ~  • ~-like adjective  II. transitive verb  Date: 13th century  1.  a. to provide, cover with, or surround with or as if with a ~ ~ in the garden  b. to separate by or as if by a ~ ~ed off half the house  2.  a. immure ~ed the monster up within the tomb — E. A. Poe  b. to close (an opening) with or as if with a ~  III. verb  Etymology: Middle English (Scots) wawlen, probably from Middle English wawil- (in wawil-eghed ~eyed)  Date: 15th century  intransitive verb of the eyes to roll in a dramatic manner  transitive verb to roll (one's eyes) in a dramatic manner