Persona Non Grata
Defined in 3 dictionaries — Cyclopedic (1922), Ballentine's (1916), Black's (1910)
The Cyclopedic Law Dictionary
Walter A. Shumaker and George Foster Longsdorf; ed. James C. Cahill · 1922
A person not acceptable. Applied to diplomatic representatives who are not acceptable at the court to which they are accredited. PERSONA REGIS MERGITUR PERSONA
Ballentine's Law Dictionary
James A. Ballentine · 1916
A person not acceptable.
Black's Law Dictionary
Henry Campbell Black, M.A. · 1910
In international law and diplomatic usage, a person not acceptable (for reasons peculiar to himself) to the court or government to which it is proposed to accredit him in the character of an ambassador or minister.
Defined under Persona in Black's Law Dictionary.