COMMON If something makes your blood boil, it makes you very angry. This statement is untrue and makes my blood boil. It makes my blood boil. He doesn't like the players yet he's always trying to interfere. Note: You can also simply say that your blood boils, meaning you are very angry. My blood boiled, but I tried to answer as simply and directly as possible. Note: In medieval times, some people believed that certain emotions changed the temperature of the blood.