commensalism
/kəˈmɛnsəˌlɪzəm/
noun
- A relationship between two living things in which one benefits and the other is neither helped nor harmed.
- Some orchids grow on tree branches in a kind of commensalism, getting support without harming the tree.
- The relationship between cattle egrets and grazing cattle is a form of commensalism: the birds eat insects stirred up by the cattle.
- In the ocean, barnacles on a whale are an example of commensalism, as the barnacles get a place to live and the whale is unaffected.