n. In zoology, an animal that lives in an abode properly belonging to another, either at its expense, as certain insects that live in galls made by the true gall-insects, or merely as a cotenant, as a pea-crab which lives in an oyster-shell, or a sea-anemone growing on a crab's back; a commensal. See cut under cancrisocial.Having the character of an inquiline; commensal.