| 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, or to subdivide interior space, to support floors, roofs, or the like, to retain earth, to fence in an area, etc. |
| 2. | Usually, walls. a rampart raised for defensive purposes. |
| 3. | an immaterial or intangible barrier, obstruction, etc., suggesting a wall: a wall of prejudice. |
| 4. | a wall-like, enclosing part, thing, mass, etc.: a wall of fire; a wall of troops. |
| 5. | an embankment to prevent flooding, as a levee or sea wall. |
| 6. | the Wall. Berlin Wall. |
| 7. | the outermost film or layer of structural material protecting, surrounding, and defining the physical limits of an object: the wall of a blood cell. |
| 8. | Mining.
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| 9. | of or pertaining to a wall: wall space. |
| 10. | growing against or on a wall: wall plants; wall cress. |
| 11. | situated, placed, or installed in or on a wall: wall oven; a wall safe. |
| 12. | to enclose, shut off, divide, protect, border, etc., with or as if with a wall (often fol. by in or off): to wall the yard; to wall in the play area; He is walled in by lack of opportunity. |
| 13. | to seal or fill (a doorway or other opening) with a wall: to wall an unused entrance. |
| 14. | to seal or entomb (something or someone) within a wall (usually fol. by up): The workmen had walled up the cat quite by mistake. |
| 15. | climb the walls or climb walls, Slang. to become tense or frantic: climbing the walls with boredom. |
| 16. | drive or push to the wall, to force into a desperate situation; humiliate or ruin completely: Not content with merely winning the match, they used every opportunity to push the inferior team to the wall. |
| 17. | go over the wall, Slang. to break out of prison: Roadblocks have been set up in an effort to capture several convicts who went over the wall. |
| 18. | go to the wall,
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| 19. | hit the wall, (of long-distance runners) to reach a point in a race, usually after 20 miles, when the body's fuels are virtually depleted and willpower becomes crucial to be able to finish. |
| 20. | off the wall, Slang.
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| 21. | up against the wall,
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| 22. | up the wall, Slang. into an acutely frantic, frustrated, or irritated state: The constant tension in the office is driving everyone up the wall. |

wall (wôl) n.
[Middle English, from Old English weall, from Latin vallum, palisade, from vallus, stake.] wall'less adj. |
wall (wôl)
n.
An investing part enclosing a cavity, chamber, or other anatomical unit.