wall (wôl)n.1. An upright structure of masonry, wood, plaster, or other building material serving to enclose, divide, or protect an area, especially a vertical construction forming an inner partition or exterior siding of a building.2. often walls A continuous structure of masonry or other material forming a rampart and built for defensive purposes.3. A structure of stonework, concrete, or other material built to retain a flow of water.4. a. Something resembling a wall in appearance, function, or construction, as the exterior surface of a body organ or part: the abdominal wall.b. Something resembling a wall in impenetrability or strength: a wall of silence; a wall of fog.c. An extreme or desperate condition or position, such as defeat or ruin: driven to the wall by poverty.5. Sports The vertical surface of an ocean wave in surfing.tr.v. walled, wall·ing, walls 1. To enclose, surround, or fortify with or as if with a wall: wall up an old window. See Synonyms at enclose.2. To divide or separate with or as if with a wall. Often used with off: wall off half a room.3. To confine or seal behind a wall; immure: “I determined to wall [the body] up in the cellar” (Edgar Allan Poe).4. To block or close (an opening or passage, for example) with or as if with a wall.Idioms: off the wall Slang 1. Extremely unconventional.2. Without foundation; ridiculous: an accusation that is really off the wall. up the wall Slang Into a state of extreme frustration, anger, or distress: tensions that are driving me up the wall. writing/handwriting on the wall An ominous indication of the course of future events: saw the writing on the wall and fled the country.[Middle English, from Old English weall, from Latin vallum, palisade, from vallus, stake. Idiom, in reference to an incident in the Bible (Daniel 5) in which a hand writes mysterious words on the wall of Belshazzar’s banquet hall and the prophet Daniel interprets them as predicting the king’s downfall.]wall?less adj.American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.wall (w??l) n1. (Building) a. a vertical construction made of stone, brick, wood, etc, with a length and height much greater than its thickness, used to enclose, divide, or supportb. (as modifier): wall hangings. mural2. (Fortifications) (often plural) a structure or rampart built to protect and surround a position or place for defensive purposes3. (Anatomy) anatomy any lining, membrane, or investing part that encloses or bounds a bodily cavity or structure: abdominal wall. Technical name: paries 4. (Mountaineering) mountaineering a vertical or almost vertical smooth rock face5. anything that suggests a wall in function or effect: a wall of fire; a wall of prejudice. 6. bang one’s head against a brick wall to try to achieve something impossible7. drive to the wall push to the wall to force into an awkward situation8. drive up the wall slang to cause to become crazy or furious9. (Banking & Finance) go to the wall to be ruined; collapse financially10. go up the wall slang to become crazy or furious11. have one’s back to the wall to be in a very difficult situation12. See off-the-wall13. See wall-to-wallvb (tr) 14. to protect, provide, or confine with or as if with a wall15. (Building) (often foll by up) to block (an opening) with a wall16. (Building) (often foll by: in or up) to seal by or within a wall or walls[Old English weall, from Latin vallum palisade, from vallus stake] walled adj ?wall-less adj ?wall-?like adjCollins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014wall (w?l) n. 1. any of various permanent upright constructions having a length much greater than the thickness and presenting a continuous surface except where pierced by doors, windows, etc.: used for shelter, protection, or privacy. 2. an immaterial or intangible barrier, obstruction, etc., suggesting a wall: a wall of prejudice. 3. a wall-like enclosing part, thing, mass, etc.: a wall of fire; a wall of troops. 4. an embankment to prevent flooding, as a levee or sea wall. 5. Usu., walls. a rampart raised for defensive purposes. 6. the outermost film or layer of structural material protecting, surrounding, and defining the physical limits of an object: the wall of a blood cell. adj. 7. of or pertaining to a wall. 8. growing against or on a wall: wall plants. 9. situated or installed in or on a wall: a wall oven. v.t. 10. to enclose, border, etc., with or as if with a wall (often fol. by in or off): to wall in the playground. 11. to seal or fill (a doorway or other opening) with a wall: to wall an unused entrance. 12. to seal or entomb (something or someone) within a wall; immure (usu. fol. by up). Idioms: 1. climb the walls, Informal. to become tense or frantic. 2. go to the wall, a. to be defeated; yield. b. to fail in business; be forced into bankruptcy. c. to risk one’s own position to defend or protect another. 3. hit the wall, to reach a point in a long-distance race when the body’s fuels are virtually depleted and willpower becomes crucial to the ability to finish. 4. off the wall, Slang. a. unreasonable; crazy. b. eccentric; bizarre. 5. up the wall, Informal. into a state of frantic frustration. [before 900; Middle English; Old English w(e)all (c. Old Frisian, Old Saxon wal)