950: octothorp Jul 16, 2017

The symbol # goes by a number of names including 'number-sign', and 'pound-sign' on account of its being used to indicate numbers and weights, and 'hash' which is related to 'hatch', the name for artistic shading by drawing a series of intersecting lines. The technical name for this is 'octothorpe' or 'octothorp', but the origins of the name are somewhat uncertain. The combining form 'octo-' means 'eight' in reference to the points around the symbol, but the '-thorpe' is less clear. It is thought to be from the surname 'Thorpe', though no one knows why definitively. Some have speculated that this is from the name of someone who worked at a telephone company, while others believe that there is some relation to the athlete Jim Thorpe. Some have claimed that the second element instead derives from the Old English 'thorp' used in the names of British villages, but this is unlikely the case.