[ sahy, psahy ]
/ saɪ, psaɪ /
any of a family of mesons consisting of a charmed quark and a charmed antiquark.
an early name for the J/psi particle.
BEAT THE DOLDRUMS WITH THIS WORD OF THE DAY QUIZ!
We know you’ll tackle this quiz totis viribus! See how many words from the week of Oct 12–18, 2020 you get right!
Question 1 of 7
What does “Indigenous” mean?
Origin of psi particle
First recorded in 1970–75
Words nearby psi particle
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2020
British Dictionary definitions for psi particle
See J/psi particle
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Scientific definitions for psi particle (1 of 2)
[ sī, psī ]
See J/psi particle.
Scientific definitions for psi particle (2 of 2)
[ sī′prīm′, psī′- ]
An electrically neutral meson having a mass 7,213 times that of the electron and a mean lifetime of approximately 1 X 10-20 seconds, composed, like the J/psi particle, of a charm-anticharm quark pair. See Table at subatomic particle.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.