coextensive

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UK/ˌkəʊ.ɪkˈstɛn.sɪv/US/ˌkoʊ.ɛkˈstɛn.sɪv/

adjective

Having the same spatial limits or boundaries; sharing the same area.

“The city and county of San Francisco are coextensive.”

UncommonScrabble 23

Meanings

adjectivecoextensive (not comparable)

alternative co-extensive

  1. not comparableHaving the same spatial limits or boundaries; sharing the same area.

    The city and county of San Francisco are coextensive.

    1 more example

    And then there are the catch-all provisions: rules that allow police to stop drivers for conduct that complies with all the rules on the books, but that officers consider "imprudent" or "unreasonable" under the circumstances, or that describe the offense in language so broad as to make a vioation virtually coextensive with the officer's unreviewable personal judgment.

    2019, Malcolm Gladwell, Talking to Strangers

    Synonyms: coterminous

  2. not comparableOccurring over the same period of time; contemporaneous.

    His life is almost co-extensive with one of the most disastrous periods in Roman history.

    1946, Bertrand Russell, History of Western Philosophy, I.30
  3. not comparablehuman sciencesHaving the same extension—the object or set of objects to which a term refers.

    Coextensive expressions with different intensions cannot in general be substituted for one another within an expression e while preserving the extension of e (assuming that the extension of a declarative sentence is its truth value).

    1995, Jaegwon Kim, Ernest Sosa, A Companion to Metaphysics

Synonyms & antonyms

adjectiveHaving the same spatial limits or boundaries; sharing the same area.

More synonyms by meaning

adjectivebeing of equal extent or scope or duration

Synonym sets from Open English WordNet, CC BY 4.0.

Origin

  1. Proto-Indo-European*ḱe?
  2. Proto-Indo-European*ḱóm
  3. Proto-Italic*kom
  4. Proto-Italic*kom-
  5. Latincon-
  6. Latinco-
  7. Englishco-
  8. Proto-Indo-European*h₁éǵʰ
  9. Proto-Indo-European*h₁éǵʰs
  10. Proto-Italic*eks
  11. Latinex
  12. Latinex-
  13. Proto-Indo-European*ten-
  14. Proto-Indo-European*tend-
  15. Proto-Indo-European*téndeti
  16. Proto-Italic*tendō
  17. Latintendō
  18. Latinextendō
  19. Latinextēnsus
  20. Late Latinextensīvus
  21. Middle Englishextensive
  22. Englishextensive
  23. Englishcoextensive

From co- + extensive.

Full word history & related roots →
Cite this entry
APA

coextensive. (n.d.). In WatkinsX Dictionary. Retrieved November 2, 2026, from https://dictionary.watkinsx.com/word/coextensive

MLA

“coextensive.” WatkinsX Dictionary, https://dictionary.watkinsx.com/word/coextensive. Accessed November 2, 2026.

Chicago

WatkinsX Dictionary, s.v. “coextensive,” accessed November 2, 2026, https://dictionary.watkinsx.com/word/coextensive.

Source: coextensive on Wiktionary, CC BY-SA 4.0.