diplomat vs embassador

diplomat and embassador both are nouns.

Word	Noun	Adjective	Verb	Adverb
diplomat	Yes	No	No	No
embassador	Yes	No	No	No

As nouns, embassador is a hyponym of diplomat; that is, embassador is a word with a more specific, narrower meaning than diplomat:

diplomat: an official engaged in international negotiations
embassador: a diplomat of the highest rank; accredited as representative from one country to another

diplomat (noun)	embassador (noun)
an official engaged in international negotiations	a diplomat of the highest rank; accredited as representative from one country to another
a person who deals tactfully with others