radiothorium

(from the article `Hahn, Otto`) ...William Ramsay, who was interested in radioactivity. While working on a crude radium preparation that Ramsay had given to him to purify, Hahn ...
Found on http://www.britannica.com/eb/a-z/r/4

Radiothorium

• (n.) A radioactive substance apparently formed as a product from thorium.
Found on http://thinkexist.com/dictionary/meaning/radiothorium/

Radiothorium

Ra`di·o·tho'ri·um noun (Chemistry) A radioactive substance apparently formed as a product from thorium.
Found on http://www.encyclo.co.uk/webster/R/4
No exact match found