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The formal name of the forward slash punctuation, used as shorthand for the word or. It is commonly seen in phrases denoting equivalents such as his/her and and/or. It is also the fine line between the numerator and denominator in fractions, and can be considered shorthand for per, as in dollars / gallon. Another specific use is in quoting poetry to denote line divisions in running text.
From Old French, "splinter"

Taken up and treated here.