commensal

adj

1. (not-comparable)Of a form of symbiosis in which one organism derives a benefit while the other is unaffected.

   “The fish (AMPHIPRION PERCULA) "intel-intel" of the blacks, is said to be commensal (literally, dining at the same table with its host), as distinguished from the parasite, which lives on its host.”

   “With this there is also associated the grazing or herding over wider or more restricted areas, belonging either collectively or discretely to the community, of sheep, cattle, goats, or swine, and almost always the domestic fowl is commensal with man in this life.”

2. (not-comparable)Eating at the same table.

noun

1. An organism partaking in a commensal relationship.

   “The tree did indeed grow right out of the algae, as I had seen from the lifeboat. There was not the least trace of soil. Either there was soil deeper down, or this species of tree was a remarkable instance of a commensal or a parasite.”

2. One who eats at the same table.

   “Colville ordered it, and was sorry when the last of his commensals, slightly bowing him a good-night, left him alone to it.”

   “Around this tragic central figure are grouped the commensals of the Vauquer pension, Rastignac, the young law-student, with shallow purse and aristocratic connections; […].”

   “More than once I sat down to lunch or dinner with brilliant commensals, one of whom was understood to have made away with a well-known personage in order to rid the state of a bad administrator, and another had, at a secret Vehmgericht in Turkey, condemned a friend of mine, now a friend of his, to be assassinated.”