Obelus

An obelus (plural: obeluses or obeli) is a historical annotation mark in codicology that has come to have three distinct modern forms, meanings and typographical uses:

• Division sign ÷
• Dagger †
• Commercial minus sign ⁒ (limited geographical area of use)

The word "obelus" comes from ὀβελός (obelós), the Ancient Greek word for a sharpened stick, spit, or pointed pillar. This is the same root as that of the word 'obelisk'. In codicology, a (usually horizontal) obelus in the form of a dagger was used to indicate erroneous or dubious content. The third symbol is an obsolescent mark used in some European countries.

In mathematics, the ÷ symbol is mainly used in Anglophone countries to represent the mathematical operation of division (but has other meanings elsewhere) and is called an obelus in older textbooks. In modern typography, the second symbol, called a dagger mark † is used as a reference mark or footnote indicator. It also has other uses in a variety of specialist contexts.