An animal that characteristically life commensally into the nest, burrow, or dwelling place of an animal of another species.
An animal that life commensally in the nest, burrow, gall, or dwelling host to an animal of another species.
An organism that lives within a reservoir of liquid collected into the hollow of a plant stem or leaf.
A gallfly which deposits its eggs in galls created by other pests.
In zoology, an animal that lives in an abode precisely owned by another, either at its expenditure, as particular pests that inhabit galls produced by the true gall-insects, or simply as a cotenant, as a pea-crab which lives in an oyster-shell, or a sea-anemone developing on a crab's straight back; a commensal. See cut-under cancrisocial.