Theatre seating area (6)
(Other definitions for stalls that I've seen before include "Part of theatre" , "Plays for time" , "Compartments for horses" , "Evasive moves" , "Posh seats in the theatre" .)
(Other definitions for dress circle that I've seen before include "Where to see theatre-goer" , "Gallery in theatre" , "best seats" , "First level in theatre above stalls" , "Theatre part" .)