Able to be proven or supported with written evidence, records, or documents.
From document (Latin documentum, 'proof') plus the suffix -able (meaning 'capable of'). The word emerged in English by the early 20th century to describe things that could be verified through documentation.
In science and law, documentable has become almost more important than truth itself—a fact only 'counts' if you can show your work with documents, which is why scientists obsessively record everything and lawyers love paper trails.
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