Wall - Vertical structure, usually solid, that defines and sometimes protects an area

"A wall is a structure and a surface that defines an area, carries a load; provides security, shelter, or soundproofing; or is decorative. There are many kinds of walls, including:Walls in buildings that form a fundamental part of the superstructure or separate interior rooms, sometimes for fire safety Border barriers between countries Brick walls Defensive walls in fortifications Doors, mobile walls on hinges which open to form a gateway Glass walls Permanent, solid fences Precast walls Retaining walls, which hold back dirt, stone, water, or noise sound Stone walls Walls that protect from oceans (seawalls) or rivers (levees) - Wikipedia"