noun

• (usually singular in construction) A public area, especially a dining hall, at a college or university; a similar shared spaced elsewhere.
• (usually singular in construction) A central section of (usually an older) town, designated as a shared area: a common.
• (figuratively) The mutual good of all; the abstract concept of resources shared by more than one, for example air, water, information.
• The common people collectively, the third estate, the people not belonging to the nobility or clergy
• (chiefly historical) The free burghers/bourgeoisie of a given town, taken collectively.
• (euphemistic, obsolete) An outhouse.
• (obsolete, UK, Oxford University) Food served at a fixed rate from the college buttery, distinguished from battels.
• Food in general; rations.
• (UK politics, Canadian politics) The House of Commons, part of the parliament under the Westminster system of parliamentary democracy.
• A surname.