- A special sign established in 1961 for certifying foreign documents.
- Under the Hague Convention, signatory countries have agreed to recognize public documents issued by other signatory countries if those public documents are authenticated by the attachment of an internationally recognized form of authentication known as an "apostille." The apostille ensures that public documents issued in one signatory country will be recognized as valid in another signatory country.
(third-person singular simple present apostilles, present participle apostilling, simple past and past participle apostilled)
- To authenticate an official document in accordance with the Apostille Convention.