The word is French. The Greek word for Diplomat was proxenos (πρόξενος). It has Greek origin as it originates from word diplono (διπλώνω means to fold) because diplomats always gave their credententials folded.
Diplomacy / Diplomat

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The greek word Αρχή (arche) is in Anarchy means several different things but they are connected. Arche means the beginning.
Uncover the definition and origins of a diploma, a critical document evidencing the completion of educational courses and marking academic success.
Discover monarchy’s evolution from ‘monos’ and ‘arkhein’ in Greek to varied global forms, from absolute to constitutional