Wiktionary
blue chamber
n. (context idiomatic English) A forbidden room.
Usage examples of "blue chamber".
I've put you in the Blue Chamber with a nice view across the lake.
At a touchit vanished, revealing an entrance to a small blue chamber, glowing as thoughcut from the heart of some gigantic sapphire.
The solid click of its lock coincided with Elminster realizing he had to ask her what to do about the guardian of the Blue Chamber.
I ducked beneath a low arch and came into a bright blue chamber of the same crystalline substance as the rest of the place.
In a moment the panel slid to the side to reveal a blue chamber: Citizen Blue's personal convey -- ance.