# substructure

> English word · Noun · frequency rank #70,303

## Definitions
1. The supporting part of a structure (either physical or organizational; the foundation).
2. The earth or gravel that the railway tracks are embedded in.
3. Synonym of base (“the forces and relations of production that produce the necessities and amenities of life”).

## Etymology
From sub- + structure.

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