4.13 Solidi and verticals
The solidus (/, plural solidi) is known by many terms, such as the slash or forward slash, stroke, oblique, virgule, diagonal, and shilling mark. It is in general used to express a relationship between two or more things. The most common use of the solidus is as a shorthand to denote alternatives, as in either/or, his/her, on/off, s/he (she or he). The solidus is generally closed up, both when separating two complete words (and/or) and between parts of a word (s/he).
The symbol is sometimes misused to mean and rather than or, and so it is normally best in text to spell out the alternatives explicitly in cases which could be misread (his or her; on or off ). An en rule can sometimes substitute for a solidus, as in an on–off relationship. In addition to indicating alternatives, the solidus is used in other ways:
• to form part of certain abbreviations, such as a/c (account), c/o (care of), n/a (not applicable), and 24/7 (twenty-four hours a day, seven days a week)
• to replace the en rule for a period of one year reckoned in a format other than the 1 January to 31 December calendar extent: 49/8 bc, the fiscal year 2000/1
• to separate the days, months, and years in dates: 5/2/99 (see also
• to separate elements in a URL:
In scientific and technical work the solidus is used to indicate ratios, as in miles/day, metres/second. In computing it is called a forward slash, to differentiate it from a backward slash, backslash, or reverse solidus (\): each of these is used in different contexts as a separator (see
The vertical rule, line, or bar (|), also called the upright rule or simply the vertical, has specific uses as a technical symbol in the sciences (see
The English winter—ending in July | To recommence in August
A solidus may also be used for this purpose. When written lines do not coincide with verse lines it may be necessary to indicate each differently: in such cases use a vertical for written lines and a solidus for verse.
When more than one speaker or singer is indicated in a run-together extract, the break between different characters’ lines is indicated by two verticals (set closed up to each other).
In websites, spaced vertical lines are sometimes used to separate elements in a menu:
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The vertical line is used in the syntax of some computing languages and scripts, and is sometimes referred to as a pipe.