# cornerstone

/ˈkɔɹnɝˌstoʊn/ (US) · /kˈɔːnəstˌəʊn/ (UK)

Source: https://englishreference.com/word/cornerstone
Updated: 2026-08-08

## Senses

### 1. a fundamental part

noun · CEFR B2

the most important part of an idea, plan, or system that everything else is built on.

For teachers: the fundamental or essential element upon which something is based or developed.

- Trust is the cornerstone of any healthy relationship.
- Free speech is often described as the cornerstone of a democratic society, providing the necessary framework for all other civil liberties to exist.

## Examples

- Trust is the cornerstone of our friendship.
- Regular exercise is the cornerstone of her new health plan.
- The rule of law remains the cornerstone of democratic governance, ensuring that no individual stands above the established legal framework.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.