# actinium-K

> English word · Noun

## Definitions
1. Synonym of francium.

## Etymology
From the former practice of naming the steps in a decay chain sequential letters. Francium was first identified in the naturally occurring actinium series.

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