noun
plural walls
[count] a structure of brick, stone, etc., that surrounds an area or separates one area from another
the structure that forms the side of a room or building
the outer layer of something that is hollow (such as a part of the body or of a plant)
back is to/against the wall
climbing the walls
drive (someone) up a/the wall
informal :to make (someone) irritated, angry, or crazy
fly on the wall
go to the wall
informal
US :to make every possible effort to achieve something, to win, etc.
Brit :to fail because of a lack of money
hit a/the wall
informal :to reach a point at which you find it very difficult or impossible to continue
the writing/handwriting is on the wall
or see/read the writing/handwriting on the wall - used to say that it is clear that something bad will probably happen soon
up against a/the wall
informal :in a very bad position or situation
verb
walls; walled; walling
wall in
[phrasal verb]
wall (something) in or wall in (something) :to surround (something) with a wall or with something that is like a wall
wall off
[phrasal verb]
wall (something) off or wall off (something) :to separate (something) from the area around it with a wall
wall up
[phrasal verb]
wall (something) up or wall up (something) :to close off (an opening) by filling it with stone, brick, etc.
wall (someone) up or wall up (someone) :to keep (someone) as a prisoner in an enclosed space