Domain Modules

Phi's domain modules are optional vocabulary paths for speakers who want to discuss a specialized field in depth. A module adds ordinary content words, recommended compounds, semantic distinctions, and examples; it never adds particles, syntax, inflection, or a separate way to parse Phi. A module is a deeper shelf in the same library, not a second language: every word on it obeys the grammar you already know.

Every module word is an ordinary part of the lexicon. The module lexicon is the complete index, while the chapters here explain how the words work together in practice. A chapter may also teach a base word established during the same profile pass; that word appears under the explorer's base-vocabulary filter rather than in the optional module index. A module's current membership can be larger than its introduced set because older roots may later receive a specialist learning home and shared words appear in every path where they belong.

All eight active profiles now have speaker-facing chapters.