Today we explore expressions using the word “bullet.” Now, of course, a bullet is what you shoot out of gun. And it comes out fast. In fact, that used to be the way to describe the speed of the superhero Superman -- he is “faster than a speeding bullet.” And that is why very fast trains are often called "bullet trains."

Bullets are not only known for their speed. They are also known for their ability to kill.

However, not all bullets are bad. A magic bullet -- sometimes called a silver bullet -- is something that solves a difficult problem easily. We often use these two expressions in the negative, because usually there is not one thing that solves a difficult problem.

For example, let’s say a country is suffering from a weak economy. People lose their jobs. Some families lose their homes. This leads to an increase in mental and physical health issues. After many years of such conditions, people want change. So, they protest in the streets. Yet, there is no silver bullet to cure all these problems.

To take a bullet for someone is a good thing. Well, the thought behind this expression is a good thing. It means you are willing to put yourself in harm’s way to protect someone else.

This often sounds like a tough expression. Mothers might not say I’d take a bullet for their child, but they would. People in the military, however, might say, “I’d take a bullet for you, man.”

Now, we know that sweating is our body’s way of keeping cool. But we also sweat when we’re nervous. When you sweat bullets you are very nervous or anxious about something.

If you dodge a bullet, you have successfully avoided a problem -- but barely.

For example, let’s say you get up late for work. Your boss has already warned you that if you come in late again, you may get fired. When you arrive at the office, you are sweating bullets -- you are nervous and very worried that your boss will fire you. However, you need not worry. As it turns out, your boss is out sick that day. You have dodged a bullet.

To ease the pain of a difficult situation, people are sometimes asked to bite the bullet. This actually sounds like really bad advice. What is the origin of this expression?

The story may go back to the American Civil War or even earlier. War is painful. And our bodies have many natural responses to pain. We tighten our fists, tense our muscles or clench our teeth.

Back during the Civil War, pain-killing drugs were often hard to find. So, doctors working on the battlefield would give their patients a piece of wood to squeeze or something soft to bite on. Many times the nearest thing was a soft, lead bullet.

Hollywood movies helped to keep this expression alive. In old western movies, more than one rugged cowboy was seen biting a bullet, perhaps drinking some strong whiskey, while removing an arrow from his body.

But that is in the movies. In modern conversation, “biting the bullet” means to accept a difficult decision or situation. It hints that a person has been putting off this difficult decision.