Origin of D particle
First recorded in 1975–80
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
- Either of two subatomic particles in the meson family, one neutral and one positively charged, having masses 3,649 and 3,658 times that of the electron and average lifetimes of 4.2 X 10-13 and 1.1 X 10-12 seconds, respectively. See Table at subatomic particle.
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