noun

• The point of junction between two things, in particular a support, that abuts.
• (engineering, architecture) The solid portion of a structure that supports the lateral pressure of an arch or vault.
• (engineering) A construction that supports the ends of a bridge; a structure that anchors the cables on a suspension bridge.
• (engineering) The part of a valley or canyon wall against which a dam is constructed.
• Something that abuts, or on which something abuts.
• The state of abutting.
• (architecture) That element that shares a common boundary or surface with its neighbor.
• (dentistry) The tooth that supports a denture or bridge.
• A fixed point or surface where resistance is obtained.