dress circle

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A section of seats in a theater or opera house, usually the first tier above the orchestra.

from The Century Dictionary.

• noun A portion of a theater, concert-room, or other place of entertainment, originally set apart for spectators or an audience in evening dress, but now generally used indiscriminately: in theaters, usually the first gallery or circle above the floor.

from the GNU version of the Collaborative International Dictionary of English.

• A gallery or balcony in a theater, generally the first above the floor, in which originally dress clothes were customarily worn.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun a curved section or tier of seats in a hall or theater or opera house; usually the first tier above the orchestra