So why is it called a ceiling rose?
The rose has symbolised secrecy since Roman times (apparently due to a confused association with the Egyptian god Horus)
Sub Rosa (latin) “under the rose” – in confidence – from the practice in diplomacy during the Middle Ages of hanging a rose over a meeting as a sign of confidentiality and freedom to speak candidly.
Through its promise of secrecy, the rose, suspended above a meeting table, symbolises the freedom to speak plainly without repurcussion. The physical carving of a rose on a ceiling was used for this purpose during the rule of England’s Tudor King Henry VIII and has over the centuries evolved into a standard item of domestic vernacular architecture, to such an extent that it now constitutes a term for the circular device that conceals and comprises the wiring box for an overhead light fitting.