set theory

noun

the branch of mathematics that deals with relations between sets.

Origin of set theory

First recorded in 1940–45

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for set theory

set theory

noun

maths the branch of mathematics concerned with the properties and interrelationships of sets

logic a theory constructed within first-order logic that yields the mathematical theory of classes, esp one that distinguishes sets from proper classes as a means of avoiding certain paradoxes

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