Word.ws English Dictionary

oct-

oct- prefix: used for the digit eight to form systematic element names of elements whose existence has been predicted, and which have not yet been given a trivial name. Also the form of octa- or octo- used before a vowel.

Prefix

oct-

  1. Used for the digit eight to form systematic element names of elements whose existence has been predicted, and which have not yet been given a trivial name.
    • un- (“1”) + bi- (“2”) + oct- (“8”) + -ium (element suffix) → unbioctium (“element 128”)

Also used as

oct- is also the form of octa- or octo- used before a vowel.

Questions about oct-

What does oct- mean?
Oct- means used for the digit eight to form systematic element names of elements whose existence has been predicted, and which have not yet been given a trivial name.
What part of speech is oct-?
Oct- is a prefix.

Words near oct- in the dictionary

  1. OCRs
  2. OCS
  3. Ocsenas
  4. OCSO
  5. oct
  6. oct-
  7. Oct.
  8. octa
  9. octa-
  10. octaacetate
  11. octaacetates

Source and license

Adapted from Wiktionary: oct- (page history and authors). Text available under the Creative Commons Attribution-ShareAlike 4.0 license. Word.ws reformatted the entry and added links. Wiktionary data of 2026-09-02.

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Cite this entry: “oct-.” Word.ws, https://word.ws/oct-. Based on Wiktionary, CC BY-SA 4.0.