or U 238


Definition for u-238 (2 of 2)

uranium 238

noun Chemistry.

the radioactive uranium isotope having a mass number 238, comprising 99.28 percent of natural uranium: used chiefly in nuclear reactors as a source of the fissionable isotope plutonium 239.

Origin of uranium 238

First recorded in 1940–45
Also called U-238, U 238.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2020

Examples from the Web for u-238

  • If you can use your demons to separate U-235 from U-238, you can use them for separating gold from sea water.

    A Feast of Demons|William Morrison
  • I could use it for separating U-235 from U-238 just as easily.

    A Feast of Demons|William Morrison