# substratum

> English word · Noun · IPA /səbˈstrɑ.təm/ · frequency rank #72,796

## Definitions
1. A layer that lies underneath another.
2. The underlying cause or basis of something.
3. A substrate.

## Etymology
Learned borrowing from New Latin substrātum, nominalisation of the neuter of Latin substrātus, perfect passive participle of substernō. By surface analysis, sub- + stratum.

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