stillhidden

Stillhidden is a term used in digital privacy and data security discourse to describe information or attributes that remain unrevealed despite access to accompanying data or outputs. It denotes persistent concealment arising from design choices, cryptographic protections, or the inherent opacity of data processing.

Origin and usage: The phrase is informal and not tied to a formal standard. It began appearing in online privacy discussions and security testing literature in the 2010s. It is often used to distinguish data that is not disclosed by a system from data that is simply hidden or encrypted; stillhidden data is not exposed by typical outputs and is not readily inferable from released data.

Applications: In privacy-preserving systems, stillhidden characteristics may include certain metadata, exact location coordinates, or user attributes protected by access controls. Techniques that support a stillhidden status include data minimization, aggregation, differential privacy, encryption, and strict access control. For example, an analytics interface may provide aggregate counts while leaving individual-level attributes stillhidden.

Limitations: The term lacks formal definition and can be interpreted variably. Critics argue that without explicit criteria, assessing what remains stillhidden or assessing the risk of disclosure is difficult. In practice, stillhidden is used as a descriptive label rather than a measurable metric.

See also: data privacy, differential privacy, data minimization, encryption, access control.