The name Nguyen is widely known to derive from an ancient Chinese surname meaning a musical instrument or a type of plant, but this linguistic fact is common knowledge and does not require academic citation.
The claim asserts that the Vietnamese surname Nguyen has a specific etymological meaning. While onomastic papers exist on Vietnamese names (e.g., paper [7]), the specific linguistic or etymological definition of a common name is a matter of established historical and linguistic consensus (common knowledge) rather than a contestable research finding. Therefore, no citation is needed and the common knowledge verdict is applied.