What are the examples of understatement?
An understatement is a comment that does not reflect true severity of a situation. An example might be to say, "The North Pole is chilly." The word "chilly" does not effectively indicate how cold it is at the North Pole.
To say that the Nazis killed several thousand Jews is a huge understatement. His admission that he had some troubles as a teen was a vast understatement, as he was twice questioned concerning gang killings. An understatement is explaining something in simple or trivial terms when, in fact, the idea being explained is complex. To say it's cold outside today, is an understatement.
No. An understatement is litotes, a statement which minimizes what it is talking about. "The United States has some debt problems" is an understatement because the United States has a huge debt problem. "Robert Wadlow was a bit taller than the average" is an understatement because he was the tallest man ever. An incomplete expression is one which is not finished. "Oh, for--! Give me that!" includes an incomplete expression.