On 9 July 2016 at 09:22, Doug McIlroy wrote: > If 19961 is the oldest citation the OED can come up with, "slash" > really is a coinage of the computer age. Yet the character had > been in algebra books for centuries. The oral tradition that underlies > eqn would be the authority for a "solid" name. I suspect, though, > that regardless of what the algebra books called it, the name > would be "divided by". Out of curiosity, I consulted Cajori [1]. All sorts of notations were used to denote division (including reversed letters) in antiquity although fractions were commonly denoted by numerator above a separating line and denominator below. In 1659, Johann Heinrich Rahn introduced the symbol ÷ (period above and below a minus sign, Unicode 00F7 -- apologies if the symbol does not display) for division, having been previously used to indicate subtraction. In 1684, G.W. Liebniz introduced ':' for division. Later authors used both solidus and reverse-solidus to indicate division. (Frustratingly, Cajori never gives a name to the symbol '/'.) Here is the start of Para. 240 (shades of Algol vs C): "There are perhaps no symbols which are as completely observant of political boundaries as are ÷ [Unicode 00F7] and : as symbols for division. The former belongs to Great Britain, the British dominions, and the United States. The latter belongs to Continental Europe and the Latin-American countries." In 1923, the US National Committee on Mathematical Requirements recommended dropping ÷ (Unicode 00F7) in favour of the symbol '/' (again nameless). Bemer, an IBM engineer, argued that the Selectric type ball should be designed to carry 64 characters required for ASCII, rather than the typewriter standard 44 (http://www-03.ibm.com/ibm/history/ibm100/us/en/icons/selectric). The suggestion was dismissed. Knuth, in his TeXbook, refers to "non-mathematical slashes" and entries for virgule and solidus say "See slash". [1] A History Of Mathematical Notations Vol I N.