n.1 an accredited diplomat sent by a State on a mission to, or as its permanent representative in, a foreign country.
2 a representative or promoter of a specified thing (an ambassador of peace).
Phrases and idioms:
ambassador-at-large US an ambassador with special duties, not appointed to a particular country.
Derivatives:
ambassadorial adj. ambassadorship n.
Etymology: ME f. F ambassadeur f. It. ambasciator, ult. f. L ambactus servant