asseverate

/əˈsɛvəˌreɪt/
verb
  1. To state something very seriously and emphatically, often in a formal or solemn way.
    • He asseverated that the information was true, despite doubts.
    • The witness asseverated that he had seen the accident clearly.
    • She asseverated her commitment to the project in front of the board.
Antonyms
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