Dictionary.com
Thesaurus.com
Synonyms

codex

American  
[koh-deks] / ˈkoʊ dɛks /

noun

codices plural
  1. a quire of manuscript pages held together by stitching: the earliest form of book, replacing the scrolls and wax tablets of earlier times.

  2. a manuscript volume, usually of an ancient classic or the Scriptures.

  3. Archaic. a code; book of statutes.


codex British  
/ ˈkəʊdɛks /

noun

  1. a volume, in book form, of manuscripts of an ancient text

  2. obsolete a legal code

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of codex

1575–85; < Latin cōdex, caudex tree-trunk, book (formed originally from wooden tablets); cf. code

Explanation

A codex is an ancient book made of stacked, hand-written pages. A historian might study a medieval codex full of beautiful calligraphy and illustrations decorated with gold leaf. The ancient Romans invented the codex. When the codex first appeared as a way to bind a manuscript, it was a great improvement over previous methods. One of these was the scroll, a long roll of paper, and another was a wax tablet. Codex is a Latin word used to mean "book of laws," although it's literally "tree trunk." The plural of codex is codices.

Keep Reading on Vocabulary.com

Vocabulary lists containing codex

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Spend a few hours in Claude Code or Codex.

From Slate • May 24, 2026

OpenAI said in its blog post it added the instruction to curb Codex and its underlying model's "strange affinity for goblins".

From BBC • Apr. 30, 2026

The e-commerce giant said on Tuesday that OpenAI models and its Codex tool will be available from Amazon cloud.

From Barron's • Apr. 28, 2026

The company’s coding tool Codex is growing quickly in popularity, and it is shaving costs by cutting other projects such as its video-generation app Sora.

From The Wall Street Journal • Apr. 28, 2026

After my previous experience on the horns I had familiarized myself with the Rerum Codex, the University’s official rules.

From "The Name of the Wind" by Patrick Rothfuss

Vocabulary.com logo
by dictionary.com

Look it up. Learn it forever.

Remember "codex" for good with VocabTrainer. Expand your vocabulary effortlessly with personalized learning tools that adapt to your goals.

Take me to Vocabulary.com