uraninite

[yoo-ran-uh-nahyt, -rey-nuh-]
noun
  1. a mineral, probably originally uranium dioxide, UO2, but altered by radioactive decay, and usually containing uranium trioxide, lead, radium, and helium, occurring in several varieties, including pitchblende: the most important ore of uranium.

Origin of uraninite

First recorded in 1875–80; uran(ium) + -in2 + -ite1
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

British Dictionary definitions for uraninite

uraninite

noun
  1. a blackish heavy radioactive mineral consisting of uranium oxide in cubic crystalline form together with radium, lead, helium, etc: occurs in coarse granite. Formula: UO 2

Word Origin for uraninite

C19: see uranium, -in, -ite 1
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