Domain - Tradução em português

hey guys, how's everyone going?

I need some help here, because I'm reading a book in english and I couldn't translate one word: "domain". Here's the whole sentece:

"As he approached the half-open door to the spacious bathroom, a domain of gold-veined white marble and large expanses of mirror, he thought that he heard sussurant voices or perhaps the slightering noise that had arisen within the wall during the night."

I know one meaning that is "domínio" but I think it can be because the sentence gets no meaning at all. I try to look on the internet but the results didn't show anything that I haven't known.

Thanks in advance.