1711, "pertaining to documents, texts, charters," from Medieval Latin diplomaticus, from diplomat-, stem of diploma (see diploma).
Meaning "pertaining to international relations" is recorded from 1787, apparently a sense evolved in 18c. from the use of diplomaticus in Modern Latin titles of collections of international treaties, etc., in which the word referred to the "texts" but came to be felt as meaning "pertaining to international relations." In the general sense of "tactful and adroit," it dates from 1826. Related: Diplomatically.
1. The Kremlin is still insisting on a diplomatic solution to the crisis.
2. He proposed a new diplomatic initiative to try to stop the war.
3. My limited diplomatic skills were tested to the utmost.
4. The two sides would like to see the normalisation of diplomatic relations.
5. The President's envoy set off on another diplomatic trip.