# that is

> English word · Adverb

## Definitions
1. In other words; that is to say. Used to introduce a clarification or explanation

## Etymology
From Old English þæt is.

## Source
Compiled from Wiktionary via kaikki.org (CC BY-SA). Data vintage: 2026-09-02.
Canonical page: https://plainspell.com/en/word/that-is