from The American Heritage® Dictionary of the English Language, 4th Edition
- n. Any of various units of matter below the size of an atom, including the elementary particles and hadrons.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. any of many units of matter smaller than an atom
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. a body having finite mass and internal structure but negligible dimensions
Sorry, no etymologies found.