The guiding principle of the Romulan warrior nuns of the Qowat Milat, who speak every thought and feeling openly, in deliberate contrast to their people's habit of secrecy.
The Way of Absolute Candor is the discipline of the Qowat Milat. Its followers hold nothing back and allow no gap between what they think and what they say. Among Romulans, who guard even their true names, this is a radical stance.
It is explored in the Picard episode Absolute Candor. Jean-Luc Picard returns to Vashti, where he once helped resettle refugees, to ask the sisters for a fighter. Elnor, the orphan boy they raised, weighs the request by their rule. A Qowat Milat binds their sword only to a cause that is lost.
Elnor's bluntness is a source of both comedy and feeling in the series. The creed returns in Discovery, where Gabrielle Burnham, by then a member of the order on Ni'Var, applies it to her own daughter in Unification III.