A galleria is a common name for a shopping mall. In the movie "Clueless," Cher spends so much time in the shopping mall, looking at clothes, etc., that when her friend Josh sees Cher outside the mall, Josh asks Cher "Who's watching the galleria?" The point that Josh is trying to make is that without Cher in the mall, there must be no one else in the mall (galleria) to watch, guard, look it over. It is a joke. But like most jokes, it has some truth to it. In the movie Cher is vain, overly concerned with her appearance and the clothes she wears, that she spends way too much time in the mall.

Yeah I heard it was really popular~

Love that movie!

ignorant to say，I guess