bordello
Synonym discussion
Sense: noun/1
'Bordello' and 'brothel' point to the same kind of place, but they create different tones. 'Brothel' is the neutral modern word and fits news reports, classroom explanations, and formal discussion. 'Bordello' often sounds older, more literary, or slightly theatrical, so it appears easily in historical fiction or stylized narration. 'Whorehouse' is rougher and more insulting because it uses a strongly derogatory word for the workers. 'House of prostitution' is the most formal and explicit option, especially in legal or official language. If you want the meaning without extra colour, choose 'brothel'; choose 'bordello' when the older or literary flavour matters to the scene.
Etymology
'Bordello' entered English from continental European forms related to French 'bordel' and Italian 'bordello'. Those words were linked to the idea of a small hut or house before narrowing to a place used for paid sex. In modern English, the word usually keeps a historical or literary feel rather than sounding neutral.