Litotes—a form of understatement that involves making an affirmative point by denying its opposite. It's often used to convey modesty or soften a statement. Litotes is usually a form of sarcasm:

‘He's not a bad singer' implies he is quite good without directly stating it.

‘It's not the worst idea,' suggests that while not perfect, the idea has merit.

Litotes can be a powerful rhetorical tool in speeches and writing, adding subtlety and nuance to your messages.

Try using litotes to add a layer of sophistication to your arguments or when you wish to temper your assertions to appeal to a wider audience.