* Astonishment is a strong feeling of surprise or amazement, often accompanied by a sense of wonder or awe. It's a heightened emotional state.
* Understatement is a figure of speech where you intentionally minimize the importance or significance of something. It's a downplaying of the reality and often used for humorous or ironic effect.
While they are opposite in terms of how they express something, they can be used together in a creative way. For instance, someone might react to a truly astonishing event with a simple "Well, that was interesting," using understatement to highlight the surprising nature of the event.
Essentially, astonishment might inspire the use of understatement as a way to express the magnitude of the situation while holding back on overtly emotional language.