1. (Historical) A manuscript book, especially of Scripture, classics, or ancient records, bound in pages rather than a scroll. Plural: codices.

2. (By extension) A structured body of knowledge or code — a collection of laws, principles, or authoritative texts.

3. (SIGNA usage) The Codex — SIGNA’s official email transmission channel and knowledge archive. A weaponized newsletter delivering brand strategy, cultural analysis, and creative intelligence directly from the House of SIGNA. Subscribers receive transmissions that deconstruct trends, decode signals, and explore how brands are built, broken, and reborn. Etymology: Latin codex (“tree trunk, block of wood”), later meaning “book” — the root of “code” and “codify.”