'Pitchblende' definitions:

Definition of 'pitchblende'

(from WordNet)
noun
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 [syn: uraninite, pitchblende]

Definition of 'Pitchblende'

From: GCIDE
  • Pitchblende \Pitch"blende`\, n. [1st pitch + blende.] (Min.) A pitch-black mineral consisting chiefly of the oxide of uranium; uraninite. See Uraninite. [1913 Webster]