The VOA Learning English program Words and Their Stories explores expressions often heard in American English. And sometimes we get it wrong.

But there are some expressions that most native English speakers use incorrectly. The problem with these terms is that, over the years, they have been shortened and important words are missing.

Here’s an instance of an idiom whose original meaning is actually opposite from how we use it today.

That idiom is: Blood is thicker than water.

Most people would characterize this as a way of saying that family relationships are the most important. The blood you share with your relatives represents a strong relationship. We call these family ties.

“Water,” in this definition of the statement, represents the connections you have with people with whom you do not share blood ties. And those links simply are not as strong.

The word “thick,” in this idiom, does not mean the physical size of something, as in: The walls on the house are very thick. Instead, it refers to the closeness of the relationship you may have with another person. If you are “thick” with your best friend, you trust him. You could even say you two are “tight.”

“Thick” shows up this way in a few other idioms. If two friends are “thick as thieves,” they are very close and trust each other a lot. When you steal from others and get caught, you will probably go to jail. So, it is important to trust the people you steal with. If one tells secrets about the others, you could all end up in jail!

The bond between thieves goes beyond a normal friendship. But for us non-thieving people, it’s also important to be there for our friends. If you are a supportive friend, you see your friends through good times and bad. Another way to say this is to “see them through thick and thin” or “be with them through thick and thin.”

So, the idiom “blood is thicker than water” means family ties are the strongest. That makes sense, right?

Well, it makes sense until you hear the whole idiom as it was first written in the Bible. The original saying is: “Blood of the covenant is thicker than water of the womb.”

The important words in the original version are the ones dropped over the centuries: “covenant” and “womb.”

A “covenant” is a serious official agreement or promise. Usually, we only use the word “covenant” when the agreement is important, such as a “covenant with God” or “the covenant of marriage.” Covenants often involve legal requirements, such as an “international covenant on human rights.”

In our Bible-based idiom, the covenant is between soldiers on the battlefield. So we don’t use the term lightly.

A “womb” is a uterus, the organ where a woman carries an unborn baby. The water in the womb protects the fetus as it grows during pregnancy. And when a pregnant woman’s water breaks, she will soon give birth.

The English language has other idioms that contain the word “womb.” For example, “womb to tomb” means from birth to death. A tomb is a building above or below the ground where we keep dead bodies. We often use “womb to tomb” when talking about government policies that protect a person for his or her entire life.

Another way we say this is “from cradle to the grave.” A cradle is a bed for a baby. And a grave is a hole in the ground for burying a dead body. So, “womb to tomb” and “cradle to grave” are both ways to refer to a person’s entire life, but in a more dramatic way. 
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