separatrix

/ˈsɛpəˌreɪtrɪks/

A separatrix is a punctuation mark that separates alternative words, like "either/or" and "he/she/they."

You probably call a separatrix a slash, but other terms for this mark are solidus and virgule. It's used for fractions in math, and to indicate dates like 10/14/2025. A separatrix is also shorthand for the word or: "Do you like me? Yes/No." In proofreading, this mark indicates a replacement word or sentence for text that's been crossed out. Separatrix has a Latin root that means "to pull apart or separate."

Definitions of separatrix

1. noun

   a punctuation mark (/) used to separate related items of information such as words, lines of text, or numbers
   synonyms: diagonal, slash, solidus, stroke, virgule

   type of:

   punctuation, punctuation mark

   the marks used to clarify meaning by indicating separation of words into sentences and clauses and phrases