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The Latin phrase sub rosa means “under the rose” and is used in English to denote secrecy or confidentiality, similar to the Chatham House Rule. The rose as a symbol of secrecy has an ancient history. …
In current times, the term is used by the Scottish Government for a specific series of “off the record” meetings.
More recently, “sub rosa” activities have become a byword for covert operations, usually by security services. Originating primarily in the Canadian and American special forces, this meaning has been gradually spreading to other countries and in particular the United Kingdom. To refer to covert operations, the Special Boat Service uses the term in the vernacular.
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