Vinculum (symbol)

Vinculum (symbol)

A vinculum is a horizontal line used in mathematical notation. It may be placed over a mathematical expression to indicate that it is to be considered grouped together, or alternatively it may function as a binary connective between arguments appearing above and below it. Vinculum is Latin for "bond", "fetter", "chain", or "tie", which is roughly suggestive of some of the uses of the symbol. The vinculum was developed in the 12th century by the Moroccan mathematician Abu Bakr al-Hassar.