co·​ho·​mol·​o·​gy (ˌ)kō-hō-ˈmä-lə-jē How to pronounce cohomology (audio)
: a part of the theory of topology in which groups are used to study the properties of topological spaces and which is related in a complementary way to homology theory

called also cohomology theory

cohomological adjective

Examples of cohomology in a Sentence

Recent Examples on the Web This was the case with Grothendieck, with his application of sheaf cohomology to geometry. Quanta Magazine, 13 Mar. 2024 Introduction Not all cohomology classes are created equal, however. Leila Sloman, Quanta Magazine, 16 Feb. 2023 On the doughnut, cohomology classes are simply loops. Leila Sloman, Quanta Magazine, 16 Feb. 2023 Feynman diagrams can be translated into geometric spaces that are amenable to analysis by cohomology. Quanta Magazine, 20 Aug. 2020

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'cohomology.' 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

circa 1959, in the meaning defined above

Time Traveler
The first known use of cohomology was circa 1959

Dictionary Entries Near cohomology

Cite this Entry

“Cohomology.” Dictionary, Merriam-Webster, Accessed 26 May. 2024.

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