Definition of "particle" []

• A very small piece or part; a tiny portion or speck. (noun)
• A very small or the smallest possible amount, trace, or degree: not a particle of doubt. (noun)
• Physics A body whose spatial extent and internal motion and structure, if any, are irrelevant in a specific problem. (noun)
• Physics An elementary particle. (noun)
• Physics A subatomic particle. See Table at subatomic particle. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "_The vast emptiness which surrounds the universe, was not filled with things seen, with sun or moon or stars; it stretched boundless, penetrating everywhere, disuniting everything, body from body, particle from particle_."
• "The same phenomenon occurs when the gamma particle is absorbed in the receiving nucleus."
• "Hm. Instead, they use some very beautiful dimensional analysis to come up with a new dimensionless parameter, what they call the particle momentum number Pa, which seems to capture more of the physics here - for very large and very small values of Pa, the particles augment turbulence, while for an intermediate range of Pa turbulence is attenuated."