![thorium dioxide thorium dioxide](https://www.tekportal.net/wp-content/uploads/2018/11/thorium-dioxide.png)
noun Chemistry.
- a white, heavy, water-insoluble powder, ThO2, used chiefly in incandescent mantles, as the Welsbach gas mantle.
noun
- a heavy insoluble white powder used in incandescent mantles. Formula: ThO 2Also called: thoria
noun
- another name for thorium dioxide