envoy vs minister plenipotentiary

envoy and minister plenipotentiary both are nouns.

Word	Noun	Adjective	Verb	Adverb
envoy	Yes	No	No	No
minister plenipotentiary	Yes	No	No	No

As nouns, envoy and minister plenipotentiary are synonyms defined as:

envoy and minister plenipotentiary: a diplomat having less authority than an ambassador

Other synonyms of envoy include envoy extraordinary.

envoy (noun)	minister plenipotentiary (noun)
a brief stanza concluding certain forms of poetry	a diplomat having less authority than an ambassador
a diplomat having less authority than an ambassador
someone sent on a mission to represent the interests of someone else