Idiom of the week: Make someone’s blood boil.
Definition: Make someone feel very angry.
Example: “When Jane found out her boyfriend cheated on her, it made her blood boil.”

It is difficult to find a clear origin of this expression. However, some possible explanations have been mentioned throughout history.
On the one hand, it is said that many years ago, scientists thought that when people got angry or excited, their blood actually boiled in their bodies.
On the other hand, there are those who claim that the idiom started being used because when we get extremely angry, we often feel hot and our skin becomes red.
Whether one or the other account is the real origin, no one can be certain. But what it is known for sure is that there is always something that makes us really angry. So, what makes your blood boil?