commensal
adjective
com·men·sal kə-ˈmen(t)-səl 
: of, relating to, or living in a state of commensalism
commensal organisms
commensal noun
Did you know?
Commensal types, be they human or beast, often "break bread" together. When they do, they are reflecting the etymology of commensal, which derives from the Latin prefix com-, meaning "with, together," jointly and the Latin adjective mensalis, meaning "of the table." In its earliest English uses, "commensal" referred to people who ate together, but around 1870, biologists started using it for organisms that have no use for a four-piece table setting. Since then, the scientific sense has almost completely displaced the dining one.
Examples of commensal in a Sentence
Recent Examples on the Web
This process called a commensal pathway in animal domestication occurs when the animal is attracted to human settlements, instead of humans actively trying to recruit the animals. —
Laura Baisas, Popular Science, 11 June 2025 According to some biologists, this might show that these birds are on their way to becoming commensal with humans—benefiting from living closely alongside them—like pigeons have in urban areas. —Jorge Garay, Wired News, 29 May 2025 Dreamtime by Simon Theuma This small, commensal shrimp almost appears to be swimming over a tapestry, but in reality, the technicolor backdrop is the body of a mosaic sea star. —Carlyn Kranking, Smithsonian Magazine, 25 Jan. 2024 Science defines the rat’s relationship to humans as commensal: an association between two species in which one benefits and the other is neither helped nor harmed. —WIRED, 7 Oct. 2023 In fact, it’s become clear that many of these commensal bacteria use the glycans studding mucin molecules as a primary source of energy. —Diana Kwon, Discover Magazine, 9 July 2019
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Laura Baisas, Popular Science, 11 June 2025 According to some biologists, this might show that these birds are on their way to becoming commensal with humans—benefiting from living closely alongside them—like pigeons have in urban areas. —Jorge Garay, Wired News, 29 May 2025 Dreamtime by Simon Theuma This small, commensal shrimp almost appears to be swimming over a tapestry, but in reality, the technicolor backdrop is the body of a mosaic sea star. —Carlyn Kranking, Smithsonian Magazine, 25 Jan. 2024 Science defines the rat’s relationship to humans as commensal: an association between two species in which one benefits and the other is neither helped nor harmed. —WIRED, 7 Oct. 2023 In fact, it’s become clear that many of these commensal bacteria use the glycans studding mucin molecules as a primary source of energy. —Diana Kwon, Discover Magazine, 9 July 2019
Cite this Entry
“Commensal.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.grautoblog.com/dictionary/commensal. Accessed 23 Apr. 2026.
Copy CitationKids Definition
commensal
adjective
com·men·sal kə-ˈmen(t)-səl
: relating to or living in a state of commensalism
Medical Definition
commensal
adjective
com·men·sal kə-ˈmen(t)-səl
: of, relating to, or living in a state of commensalism
commensal noun
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