Slang the topmost balcony section in a theater, where the cheaper seats are located
See peanut gallery in American Heritage Dictionary 4
The hindmost or uppermost section of seating in a theater balcony, where the seats are cheapest.
A group of people whose opinions are considered unimportant: “Pressure is building … to force … Alan Greenspan to cut interest rates and pump up the money supply. [He] has politely ignored these catcalls from the peanut gallery”(H. Erich Heinemann).