co-

co- — prefix

1. added to the start of a word to show that two or more people or things do someth

1.字首B1
釋義

added to the start of a word to show that two or more people or things do something jointly, share a role, or work alongside one another

例句

Eitan and Tariro became co-founders of the language-learning app last spring.

co- + noun: co-founder (joint role)

Elena agreed to co-write the textbook chapter with her old supervisor.

co- + verb: co-write (do an action jointly)

同義詞
  • joint-

    less productive as a prefix; usually appears as a separate adjective (joint owner) rather than fused

  • fellow-

    older, more formal; emphasizes shared membership (fellow worker) rather than shared role

文法句型

co- + noun (co-author, co-founder)

co- + verb (co-write, co-produce)

用法筆記

Attaches freely to nouns and verbs to create new joint-role or joint-action words. A hyphen is often used, especially before a vowel (co-owner, co-author), though some long-settled words drop it (coexist, cooperate).

常見錯誤

❌He is the co of the company.
✅He is the co-founder of the company.
💡co- is a prefix, not a standalone word; it must attach to another word.
❌cooperator wrote the report together
✅The co-authors wrote the report together.
💡pick the standard joint-role term (co-author) rather than stitching co- onto any noun.

co- — abbreviation

co- — abbreviation