IPA: /ˌdɪpləˈmætɪk/
KK: /ˌdɪpləˈmætɪk/
Relating to managing relationships between countries or being tactful and sensitive when dealing with people.
The ambassador took a diplomatic approach to resolve the conflict between the two nations.
Diplomatic → It is formed from "diploma" (from Greek "diplōma", meaning folded paper or document) and the suffix "-atic" (meaning pertaining to). The word "diplomatic" refers to matters pertaining to official documents or negotiations between states.
Think of 'diploma' as a formal document, and remember that 'diplomatic' relates to the formal dealings and negotiations between countries.