Living on or within another organism, and deriving benefit without injuring or benefiting the other individual.
An organism living on or within another, but not causing injury to the host.
This adjective is used to describe a situation in which several people eat together. The word comes from two Latin words, the preposition cum, meaning together or with, and the noun mensa, meaning table. Commensal therefore literally means that dinner guests are brought together by their table. Introduced in the fifteenth century, the word can also be used as a noun; if you are dining with a mysterious someone tonight, you can refer to him or her as your commensal.
In biology, an organism that lives on or in or with another, usually using the same food, but is not truly a parasite.
An animal or plant which lives on another animal or plant but does not harm it in any way. Both may benefit from the association.
A normally harmless organism or bacterium that lives in or on the body. Commensals may cause disease, but usually only in people with impaired immune systems.
An organism that lives in close association with another of a different species without either harming or benefiting it. For example, some microorganisms living in the gut obtain both food and a suitable habitat but neither harm nor benefit man.
Micro-organisms which live in or on the body (e.g. in the gut or respiratory tract, or on the skin) without doing any harm to the individual.
Either of the two organisms of different species that live in a close but nonparasitic relationship.
A microorganism or other living entity that typically resides within or on the body, neither causing harm nor providing any direct advantage to its host.