noun: (arithmetic, obsolete) Any symbol used to group some of the terms in an expression, indicating that that part of the calculation should be done before other parts.
noun: (arithmetic) A horizontal line over the top of some of the terms in an expression, indicating that that part of the calculation is to be done before other parts.
noun: (arithmetic) Specifically, the horizontal line between the numerator and denominator in a fraction.
noun: (anatomy) A ligament that limits the movement of an organ or part.
