atomic theory
noun
1
: a theory of the nature of matter: all material substances are composed of minute particles or atoms of a comparatively small number of kinds and all the atoms of the same kind are uniform in size, weight, and other properties
2
: any of several theories of the structure of the atom
especially
: one based on experimentation and theoretical considerations holding that the atom is composed essentially of a small positively charged comparatively heavy nucleus surrounded by a comparatively large arrangement of electrons
Examples of atomic theory in a Sentence
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The most famous text influenced by Democritus is De rerum natura (On the Nature of Things), the didactic poem in six books by Titus Lucretius Carus (99 BCE–55 BCE), a poet of the late Roman Republic and a follower of the Greek philosopher Epicurus, who had taken up Democritus’s atomic theory.
—
Priyamvada Natarajan, The New York Review of Books, 15 June 2021
The sprawling tale begins in ancient Greece, with the origin of atomic theory.
—Alex Orlando, Discover Magazine, 16 May 2021
Before atomic theory—which states that all matter is made up of tiny particles called atoms—people didn’t have a good idea of what matter really was.
—Caroline Delbert, Popular Mechanics, 24 Feb. 2022
But Rovelli says that the degree of confirmation of atomic theory shouldn’t even be measured in the same units as that of string theory.
—Quanta Magazine, 16 Dec. 2015
String theory is not, say, 10 percent as confirmed as atomic theory; the two have different statuses entirely.
—Quanta Magazine, 16 Dec. 2015
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Priyamvada Natarajan, The New York Review of Books, 15 June 2021
The sprawling tale begins in ancient Greece, with the origin of atomic theory.
—Alex Orlando, Discover Magazine, 16 May 2021
Before atomic theory—which states that all matter is made up of tiny particles called atoms—people didn’t have a good idea of what matter really was.
—Caroline Delbert, Popular Mechanics, 24 Feb. 2022
But Rovelli says that the degree of confirmation of atomic theory shouldn’t even be measured in the same units as that of string theory.
—Quanta Magazine, 16 Dec. 2015
String theory is not, say, 10 percent as confirmed as atomic theory; the two have different statuses entirely.
—Quanta Magazine, 16 Dec. 2015
Cite this Entry
“Atomic theory.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/atomic%20theory. Accessed 27 Feb. 2025.
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