# PKI

CEFR C2 · Noun

Source: https://englishreference.com/word/pki
Updated: 2026-07-22

## Definition

Stands for Public Key Infrastructure. A system of rules and digital tools that keeps online communication safe by proving who people and websites really are.

For teachers: Abbreviation for Public Key Infrastructure. A framework of hardware, software, policies, and procedures used to create, manage, distribute, use, store, and revoke digital certificates and manage public-key encryption.

## Examples

- The company uses PKI to secure its internal emails.
- Without a robust PKI, it would be impossible to verify the identity of websites during financial transactions.
- The security of the entire network relies on the integrity of the PKI, as any compromise of the root certificate authority would invalidate all issued digital identities.

---

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.