litotes

/ˈlaɪtəˌtiz/
noun
  1. A figure of speech that uses understatement by saying something is not the opposite of what is meant, often for ironic or humorous effect.
    • In literature, litotes can add a subtle, dry humor to a description.
    • Saying 'It's not the best weather' during a hurricane is an example of litotes.
    • She used litotes when she said the test was 'not too hard' after getting a perfect score.
Antonyms