Definitions for uraniniteyʊˈræn əˌnaɪt, -ˈreɪ nə-
Random House Webster's College Dictionary
u•ran•i•niteyʊˈræn əˌnaɪt, -ˈreɪ nə-(n.)
a radioactive mineral, uranium dioxide, UO2, usu. found mixed with its decay products: the primary ore of uranium.
Origin of uraninite:
1875–80; uran (ium ) + -in1+ -ite1
a mineral consisting of uranium oxide and trace amounts of radium and thorium and polonium and lead and helium; uraninite in massive form is called pitchblende which is the chief uranium ore
Any of several brownish-black forms of uranium dioxide, UO, (especially pitchblende) that is the chief ore of uranium; it is isomorphous with thorianite.
a mineral consisting chiefly of uranium oxide with some lead, thorium, etc., occurring in black octahedrons, also in masses with a pitchlike luster; pitchblende