a positively charged particle consisting of two protons and two neutrons, emitted in radioactive decay or nuclear fission; the nucleus of a helium atom.
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The Wittiest Vegan Names For Animal-alternativesWe know the word vegan came about in the 1800s, but what about the other terms that relate to veganism? Let's take a look at what vegans call their versions of animal products and where they came up with the names. Note: These may not be the most popular names for these vegan items, but they're definitely the most entertaining.
- alpha globulin,
- alpha granule,
- alpha helix,
- alpha iron,
- alpha male,
- alpha privative,
- alpha radiation,
- alpha ray,
- alpha receptor,
- alpha rhythm
Origin of alpha particle
First recorded in 1900–05
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
a helium-4 nucleus, containing two neutrons and two protons, emitted during some radioactive transformations
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
A positively charged nuclear particle, indistinguishable from a helium atom nucleus and consisting of two protons and two neutrons.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
A positively charged particle that consists of two protons and two neutrons bound together. It is emitted by an atomic nucleus undergoing radioactive decay and is identical to the nucleus of a helium atom. Because of their relatively large mass, alpha particles are the slowest and least penetrating forms of nuclear radiation. They can be stopped by a piece of paper. See more at radioactive decay.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.