# astatine

> English word · Noun · IPA /ˈastətiːn/

## Definitions
1. A highly radioactive chemical element (symbol At), one of the halogens, with atomic number 85.

## Etymology
From Ancient Greek ἄστατος (ástatos, “unstable”) + -ine.

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