Answer:
Understatement
Step-by-step explanation:
A hyperbole is an extreme exaggeration.
it’s an understatement, because what “he” did was extremely cruel, but is understated when the speaker describes it as “uneighborly“
example: Someone saying ”You almost killed me!” when almost getting hit by a ball=hyperbole
someone saying “it’s hot“ in a house fire=understatement