separatrix
/sɛpəˈɹeɪtɹɪks/
"separatrix" is a 10-letter English headword indexed on PlainSpell.
The verdict
“separatrix” is uncommon English (outside the top frequency list), classed as a noun. The kind of spelling people second-guess.
- Unranked
- below top-frequency English
- 10
- letters
According to Wiktionary data (CC BY-SA, analyzed September 3, 2026) - The ⟨L⟩ or pipe ⟨|⟩ mark formerly used to divide integers from decimals.
Corpus desk
Index EN-separatrix · separatrix · English
separatrix · unranked · 0 variants · 0 confusables
- FREQ-UNRANKED Unranked
- LEN-MEGA 10 letters
- VOW-4 4 vowels
- CONFUS-0 No pairs
- VAR-0 0 variants
- BOOK-THIN "S" thin
- PHOTO-UNK Peer pending
Read with this headword: Spelling guide for this pattern
Desk codes from Wiktionary headword shape, FrequencyWords rank tier, confusable-pair count, generated misspelling depth, letter-cohort book size, and photo-finish peer. Not a difficulty grade.
| Property | Value |
|---|---|
| Headword | separatrix |
| Language | English |
| Part of speech | Noun |
| IPA | /sɛpəˈɹeɪtɹɪks/ |
| Letters | 10 |
| Misspellings tracked | 0 |
| Confusable pairs | 0 |
| Source | Wiktionary (kaikki.org) |
Long-tail rank of “separatrix” in English
Rare enough to double-check
separatrix is uncommon English outside the top frequency list, classed as anoun, transcribed /sɛpəˈɹeɪtɹɪks/. Rarity is why readers land here mid-draft. 6 senses are on record.
No misspelling variants are generated for separatrix in our index, since its letter pattern doesn't lend itself to common typo substitutions. This entry stands alone in our confusable dataset, which typically means the spelling is too distinctive to be mistaken for another word.
Etymologically, the entry records: 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 de… The correct English form is separatrix, spelled S-E-P-A-R-A-T-R-I-X.
Definition
- 1The ⟨L⟩ or pipe ⟨|⟩ mark formerly used to divide integers from decimals.
- 2Synonym of decimal point, which replaced such marks.
- 3The 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.
- 4A terminator: a line on a partially-illuminated surface separating the lit and shaded regions.
- 5The line between regions having different magnetic fields.
- 6The boundary separating two modes of behavior in a differential equation.
Recorded use
Wiktionary exampleThese source excerpts show how separatrix appears in context. They illustrate usage; the definition above remains the entry’s reference meaning.
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.
Definitions, pronunciation, and etymology for this entry are drawn from Wiktionary via the kaikki.org structured extract (CC BY-SA). See the methodology for how each field is sourced and updated.