Dreaming of rats is very bad as per dream interpretation and meaning. It means there will be damage to property or some other kind of damage to things that you value most. Rats are nibblers and it means there will harm to health or wealth.
Seeing dream of several rats means you will face sudden problems in various aspect of life including relationship, studies and career.
Dreaming of dead rat is a sign of bad health. You or a family member can expect severe health issues.
Dreaming of rats running on you and all around means natural calamity. You can expect attack by poisonous animals. It also means unable to reach a particular place on time.
Seeing dream of rats being hunted or getting killed by other animals like snake etc means you will face difficulties but you will overcome them. You just need to stay focused and ignore all things that are not part of your goal.
Dreaming of rats in water means your dream of going to distant place will be fulfilled in near future.