Merriam-Webster's Word of the Day for December 17, 2012 is:
commensal \kuh-MEN-sul\ adjective
1 : of or relating to those who habitually eat together 2 : of, relating to, or living in a relationship in which one organism obtains food or other benefits from another without damaging or benefiting it
"Florentines in the 1980s still valued their families and insisted on eating together every day, even as they recognized that several forces including television, restaurants, and the rapid pace of work undermined commensal meals." From Carole M. Counihan's 2004 book Around the Tuscan Table: Food, Family, and Gender in Twentieth Century Florence
"Nunez's work on bacteria that invade the gut focuses on competition between the naturally occurring, or commensal, bacteria that live in the intestinal tract, and invading pathogens." From a press release from the University of Michigan Health System, November 1, 2012
Did you know?
Commensal types, be they human or beast, often "break bread" together. When they do, they are reflecting the etymology of "commensal," which derives from the Latin prefix "com-," meaning "with, together, jointly" and the Latin adjective "mensalis," meaning "of the table." In its earliest English uses, "commensal" referred to people who ate together, but around 1870, biologists started using it for organisms that have no use for a four-piece table setting. Since then, the scientific sense has almost completely displaced the dining one.