set theory


: a branch of mathematics or of symbolic logic that deals with the nature and relations of sets
set theoretic adjective

Examples of set theory in a Sentence

Recent Examples on the Web The first person to harness this power was Georg Cantor, the founder of the mathematical subfield of set theory. Quanta Magazine, 5 Sep. 2023 Maggie Koerth-Baker on what Christian fundamentalists have against set theory. Ed Yong, Discover Magazine, 11 Aug. 2012 His first major paper, published in 1925, set about refurbishing set theory along clean, logical lines. Samanth Subramanian, The New Republic, 8 Mar. 2022 Causal set theory, another contender for a theory of quantum gravity, posits that space and time are made of more fundamental components as well. Adam Becker, Scientific American, 20 Jan. 2022 Mathematicians and computer scientists had an exciting year of breakthroughs in set theory, topology and artificial intelligence, in addition to preserving fading knowledge and revisiting old questions. Quanta Magazine, 23 Dec. 2021 There are many different ways to construct the disjoint union using the axioms of set theory, which will not produce exactly the same set but will, necessarily, produce isomorphic ones. Emily Riehl, Scientific American, 17 Sep. 2021 The most famous example of undecidability in set theory is CH. Martin Goldstern, Scientific American, 16 Aug. 2021 It’s one of nine axioms in a system called Zermelo-Fraenkel set theory, or ZFC, that serves as the foundation of modern mathematics. Quanta Magazine, 26 Aug. 2021 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'set theory.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1936, in the meaning defined above

Time Traveler
The first known use of set theory was in 1936

Dictionary Entries Near set theory

Cite this Entry

“Set theory.” Dictionary, Merriam-Webster, Accessed 1 Oct. 2023.

Kids Definition

set theory

: a branch of mathematics that deals with sets and with relations between sets

More from Merriam-Webster on set theory

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