eta particle

[ ātə, ē ]


  1. An electrically neutral meson having a mass 1,071 times that of the electron and a mean lifetime of approximately 3.5 X 10-8 seconds. See Table at subatomic particle.

Words Nearby eta particle

The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.