Meaning Loss
When a claim becomes obsolete because its terms have shifted meaning
Meaning loss occurs when a claim becomes obsolete not because it was refuted but because the terms it uses have shifted meaning through definition drift. The claim may still be "true" under its original definitions, but those definitions are no longer in use, so the claim no longer communicates anything actionable.
This is a distinct failure mode from refutation. A refuted claim was shown to be false; a meaning-lost claim was never tested against current concepts. Treating meaning-lost claims as live knowledge creates confusion because readers interpret them through current definitions.
In a Dialectical Graph, meaning loss is tracked through the claim status taxonomy. Claims can be marked obsolete with pointers to the definition changes that severed their relevance, preserving historical context without polluting current knowledge.