neu·tron (ntrŏn′, ny-)
n. Abbr. n
The electrically neutral nucleon, a baryon composed of two down quarks and one up quark, which has a mass 1,839 times that of an electron, is stable when bound in an atomic nucleus, but has a mean lifetime of 886 seconds as a free particle. It is a basic component of all atomic nuclei except the protium isotope of hydrogen.
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Indo-European & Semitic Roots Appendices
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