Uranium Definition

A very hard, heavy, silver-colored, radioactive, metallic chemical element, one of the actinides, found only in combination, chiefly in pitchblende: symbol, U; at. no. 92: an isotope (uranium-235) undergoes neutron-induced fission and another, more plentiful, isotope (uranium-238) is used to produce plutonium.
Webster's New World
The uranium isotope with mass number 235 and half-life 7.04 × 108 years, fissionable with slow neutrons and capable in a critical mass of sustaining a chain reaction that can proceed explosively with appropriate mechanical arrangements.
American Heritage
The most common isotope of uranium, having mass number 238 and half-life 4.47 × 109 years, nonfissionable but may be irradiated with neutrons to produce fissionable plutonium-239.
American Heritage
The element with atomic number 92 and symbol U.
  • atomic number 92
  • u

Origin of Uranium

  • New Latin ūranium named by German chemist Martin Heinrich Klaproth, who discovered the element in 1789, after New Latin U̯ranus the planet Uranus, discovered in 1781 Uranus

    From American Heritage Dictionary of the English Language, 5th Edition

  • uranium + 235 the atomic mass of this isotope.

    From Wiktionary

  • After Uranus (the planet).

    From Wiktionary

Find Similar Words

Find similar words to uranium using the buttons below.

Words Starting With

Words Ending With