An understatement is otherwise called litotes. An understatement is a figure of speech where a writer or speaker deliberately makes a situation or thing seem less important or serious than it actually is. Litotes is a specific type of understatement that involves using a negative statement to express a positive sentiment. For example, saying "I'm not unhappy with my test result" instead of "I'm happy with my test result" is a use of litotes. It is often used for rhetorical effect and can convey irony or sarcasm.