# protolith

> English word · Noun · IPA /ˈpɹoʊ.təˌlɪθ/

## Definitions
1. The original precursor of any specified metamorphic rock

## Etymology
From proto- + -lith.

## Source
Compiled from Wiktionary via kaikki.org (CC BY-SA). Data vintage: 2026-05-06.
Canonical page: https://plainspell.com/en/word/protolith