The Collaborative International Dictionary
Peanut gallery \Pea"nut gal"ler*y\
the cheapest seats in a theater, being typically those farthest from the stage, as in the uppermost balcony.
in a television show for children, the section where visiting children sit as guests during the performance.
WordNet
n. (figurative) people whose criticisms are regarded as irrelevant or insignificant (resembling uneducated people who throw peanuts on the stage to express displeasure with a performance); "he ignored complaints from the peanut gallery"
rearmost or uppermost area in the balcony containing the least expensive seats [syn: second balcony, family circle, upper balcony]
Wikipedia
A peanut gallery was, in the days of vaudeville, a nickname for the cheapest (and ostensibly rowdiest) seats in the theater, the occupants of which were often known to heckle.
The least expensive snack served at the theatre would often be peanuts, which the patrons would sometimes throw at the performers on stage to show their disapproval. The phrases "no comments from the peanut gallery" or "quiet in the peanut gallery" are extensions of the name.
In 1943 the Howdy Doody children's radio show adopted the name to represent its audience of children. Howdy Doody is most remembered for its later transition to television, which continued the Peanut Gallery audience, now on camera. It is from this usage that the name of the comic strip Peanuts was derived.
Usage examples of "peanut gallery".
Ebersole ignored the profanity and the cross-talk from the peanut gallery.
Bug and some of his bitter, nutcase friends arrived with a wide selection of beer, and they were in good moods, sitting around playing peanut gallery to Hard Copy and A Current Affair, being amusing and eating half of Susan's party food while she was dressing.
Noreen was supposed to be a minor character with limited forkpoint options, but judging by the number of moves she managed to squeeze out of the peanut gallery's cheapie say-sos, Cass knew Noreen of the pouty lips thought she was the star.
If Democratic Party shills like Ben-Veniste - who himself looks like someone who ought to be searched at airports - are going to make ludicrous, macho statements like that in order to win applause from weeping widows in the peanut gallery, can't we hold them to that policy when it matters?