undocumentated

Undocumentated is an English adjective that refers to something lacking documentation or official paperwork. It is a rare and nonstandard form in most varieties of English; the preferred term in formal writing is undocumented, or not documented when referring to objects or processes.

Etymology and usage: The word appears to be formed from the noun document with the negative prefix un- and the participial suffix -ated. Because it is not widely recognized in dictionaries, its acceptability varies by style guide and audience. In technical and academic writing, undocumentated is generally discouraged in favor of undocumented.

Contexts and examples: In software development, a function or API described as undocumentated would imply there is no documentation available about its behavior or usage. In data management, undocumentated datasets lack metadata or descriptive notes. In contrast, undocumented is the standard term for lacking official documents across contexts, including for people in immigration discussions, though the latter usage is common only when referring to lacking legal status rather than a linguistic label for objects or concepts. When precision is required, writers typically choose undocumented or explicitly describe what is missing (for example, “no usage notes are provided”).

See also: undocumented, documentation, metadata, data provenance, provenance of information.