Separatrix

//sɛpəˈɹeɪtɹɪks// noun

noun ·Uncommon ·Advanced level

Definitions

Noun
  1. 1
    The ⟨L⟩ or pipe ⟨|⟩ mark formerly used to divide integers from decimals. historical

    "Therefore in writing of decimall parts let the separatrix be always used."

  2. 2
    a punctuation mark (‘/’) used to separate related items of information wordnet
  3. 3
    Synonym of decimal point, which replaced such marks. obsolete
  4. 4
    The proofreader's mark resembling a slash ⟨ / ⟩ or vertical bar ⟨ | ⟩ placed after a note in the margin to indicate that it should replace the item(s) struckthrough in the running text or to separate it from other margin notes.
  5. 5
    A terminator: a line on a partially-illuminated surface separating the lit and shaded regions.
Show 2 more definitions
  1. 6
    The line between regions having different magnetic fields.
  2. 7
    The boundary separating two modes of behavior in a differential equation.

Example

More examples

"Therefore in writing of decimall parts let the separatrix be always used."

Etymology

Learned borrowing from Latin sēparātrīx, the feminine form of separator (originally owing to an implied līnea (“line”)), from sēparāre (“to divide; to separate”) + -trix (forming female agents). By surface analysis, separate + -trix. First developed as a decimal mark among the medieval Arab mathematicians, whence a shorter variant gave rise to the decimal comma employed by many European countries and their former colonies.

Related phrases

Data sourced from Wiktionary, WordNet, CMU, and other open linguistic databases. Updated March 2026.