or U 238
When Did The Letter U Enter The Alphabet?There was no letter U in the alphabet. Well, that’s not the entire story. There was the sound for the letter we call U, but it didn’t look like U. It looked like V. The Classical Latin alphabet had only 23 letters, not the 26 that we have today. (This is why the W looks like a double V but is pronounced like a double …
Definition for u-238 (2 of 2)
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. 2019