North Korea may be famous for the bombastic, derogatory and often-awkward English phrases it uses to slam its enemies.
Dotard means a person in a feeble and childish state due to old age. It's a translation of "neukdari," a Korean word that refers to elderly people in a derogatory manner.
The Korean Central News Agency transmitted Kim's statement verbatim. It followed Trump's speech at the U.N. this week mocking Kim as a "Rocket Man" on a "suicide mission," and saying if the U.S. is "forced to defend itself or its allies, we will have no choice but to totally destroy North Korea."