Ichidan/ru-verb

1. to break (into pieces); to be broken; to be smashed
2. to collapse; to crumble; to decline; to cool (e.g. enthusiasm); to dampen (e.g. one's will to fight)
3. to become less formal; to throw off reserve; to become affable
4. to become easy to understand (e.g. a story)
5. to be worried