Commensal
<B>1.</B> Living in a relationship in which one organism derives food or other benefits from another organism without hurting or helping it.
Commensal bacteria are part of the normal flora in the mouth.<BR><B>2.</B> An intimate relationship.
The Norway rat, roof rat, and house mouse are considered commensal rodents because of their intimate relationships with humans.</P> From the Latin prefix com- (with, together, jointly) + the Latin adjective mensalis (of the table).
Commensal people eat together at the same table.