sub·​atom·​ic | \ ˌsəb-ə-ˈtä-mik How to pronounce subatomic (audio) \

Definition of subatomic

1 : of or relating to the inside of the atom
2 : of, relating to, or being particles smaller than atoms

Examples of subatomic in a Sentence

Recent Examples on the Web

Trillions of the subatomic things pass through your body and the rest of the planet every second, without disturbing any atoms. Bill Andrews, Discover Magazine, "State of Science: Neutrinos Provide a New Way to Probe the Cosmos," 1 Jan. 2019 One is quantum mechanics, which deals with the behaviour of very small things like molecules, atoms and subatomic particles. The Economist, "How Einstein and Eddington stood against jingoism," 7 June 2019 Only dark matter and certain subatomic particles like muons and neutrinos can pass through the thousands of feet of dense rock. Joe Lindsey, Popular Mechanics, "Filling the Void: What Is Dark Matter?," 28 May 2019 Light axions looking for enlightenment The version of dark matter that is the focus of this work is a hypothetical subatomic particle known as the axion. Chris Lee, Ars Technica, "Pulsars could convert dark matter into something we could see," 20 Dec. 2018 Scientists discovered in 1912 that subatomic particles — the building blocks of matter, such as protons, electrons, muons, neutrinos, and quarks — hit the Earth every day. Brian Resnick, Vox, "10 science stories in 2018 that made us go, “Whoa, that’s awesome”," 18 Dec. 2018 Isotopes such as iron-60 are telltale signs of exploding star events, as are subatomic particles called muons, which form when cosmic radiation interacts with the atmosphere. Jill Kiedaisch, Popular Mechanics, "Exploding Stars Might Have Brought an End to the Prehistoric Megalodon," 14 Dec. 2018 It's linked to the notion that a subatomic particle is in a superposition of all possible states at once, described by an equation called the wave function, until some kind of measurement is made. Jennifer Ouellette, Ars Technica, "At last! Marvel finally drops first trailer for Avengers: Endgame," 7 Dec. 2018 It’ll be taken apart and thoroughly scanned to understand how the harsh conditions of space — unpredictable levels of radiation, subatomic particles, and unstable power — can affect a commercial off-the-shelf computer. Mary Beth Griggs, The Verge, "A supercomputer on the ISS will soon be open for science experiments," 1 Nov. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'subatomic.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of subatomic

1874, in the meaning defined at sense 1

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Last Updated

26 Jun 2019

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The first known use of subatomic was in 1874

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More Definitions for subatomic



English Language Learners Definition of subatomic

: smaller than an atom
: of or relating to the inside of an atom


sub·​atom·​ic | \ ˌsəb-ə-ˈtäm-ik How to pronounce subatomic (audio) \

Medical Definition of subatomic

1 : of or relating to the inside of the atom
2 : of, relating to, or being particles smaller than atoms

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