thorium

• POS: Noun
• HYPHEN: tho=ri=um

CIDE DICTIONARY

thorium, n. [NL. See Thorite.].

 A metallic element found in certain rare minerals, as thorite, pyrochlore, monazite, etc., and isolated as an infusible gray metallic powder which burns in the air and forms thoria; -- formerly called also thorinum. Symbol Th. Atomic weight 232.0.  [1913 Webster]

OXFORD DICTIONARY

thorium, n. Chem. a radioactive metallic element occurring naturally in monazite, the oxide of which is used in gas-mantles.

Usage

Symb.: Th.

Etymology

Thor, Scand. god of thunder