Also found in: Wikipedia.
An electrically neutral baryon containing a strange quark and having a mass 2,183 times that of the electron and a mean lifetime of about 2.6 × 10-10 second.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.