‘Err on the Side of Caution’: Definition, Meaning, and Examples

Did someone say to you that it’s better to ‘err on the side of caution’? What does that mean, and where does the phrase come from?

‘Err on the side of caution’ is an idiom that means, in short, that if one is going to make a mistake, it is better to make the mistake of being too cautious rather than too risky. Basically, it is a way for someone to say that they want to choose a more prudent option rather than one that is less safe and conservative.

What Does 'Err on the Side of Caution' Mean?

‘Err on the side of caution’ is an idiomatic expression that means to act in the least risky way possible in circumstances in which one is unsure about the consequences.

Basically, if a person is given several options for how to proceed in a specific situation, ‘erring on the side of caution’ means that they are choosing the option that they perceive to be the safest and most conservative route.

Rather than taking risks, a person who ‘errs on the side of caution’ is behaving prudently.

While this seems to be a fairly straightforward phrase, there is a bit of disagreement about its precise meaning.

The reason for this has to do with a lack of consensus about the use of the word ‘err.’

Some believe that the word ‘err’ is defined in contemporary fashion, meaning “to make a mistake.” In this way, the phrase is implying that it is ultimately to make the mistake of being too cautious than to be caught in a situation where one makes the error of not being cautious enough.

On the other side of the debate are people that believe that the definition of ‘err’ should be understood as more related to the Old French word errer which carries the meaning “to stray.”

Based upon this interpretation of the meaning, the more precise explanation would be that one would stray toward the more cautious side of a path in order to avoid unnecessary risks or mistakes.

Even though there is some uncertainty about the exact meaning of the phrase, both interpretations generally imply a similar concept at their core. No matter which definition of ‘err’ you believe is correct, the expression means that one is going to lean towards the safer option rather than a riskier one.

Where Does 'Err on the Side of Caution' Come From?

Unfortunately, the phrase ‘err on the side of caution’ is one word too long to run through the Google Books Ngram Viewer. When we take a look at ‘err on the side of,’ though, we see that it has been in use since before the 1800s. It increased in usage until the early 1900s, when it decreased for the first half of the 20th century before increasing again after 1960.

When we compare ‘err on the side of’ and ‘on the side of caution’ in the Ngram Viewer, it appears that the phrase ‘err on the side of’ is more often used than ‘on the side of caution,’ which implies that books more frequently contain the idiomatic phrase ‘err on the side of’ (something) more than specifically the phrase ‘err on the side of caution.’

While ‘err on the side of caution’ might be the most well-known version of the phrase, someone might also say things like “It’s best to ‘err on the side of’ generosity” or “let’s ‘not err on the side of’ alarmism.” The preface ‘err on the side of’ essentially means prioritizing something, perhaps even unnecessarily or excessively.

Examples of 'Err on the Side of Caution' In Sentences

How would you use the idiom ‘err on the side of caution’ in a sentence? Let’s explore some examples to help you gain a better understanding of the meaning:

• “Man, time really flies when we’re at the beach. We might want to err on the side of caution and set the alarm so we don’t end up leaving too late for the movie.”
• “I know you’re eager to dive in and get our business started, but I’m hoping you can bear with me. I really feel like we should err on the side of caution until all of our permits have been granted.”
• “These tomatoes are probably fine to eat, but I’m just not sure where they came from. I think it’s best to err on the side of caution and throw them in the compost.”
• “Of course, he wants to err on the side of caution. He never wants to take any risks. That doesn’t surprise me in the slightest.”
• “Sam says we should check the air pressure in our tires before we leave to go mountain biking. When I told him I just filled them last week, he said, ‘it’s better to err on the side of caution.’”
• “I wanted to go to the Caribbean during our summer holiday break, but Tom said that we should err on the side of caution and wait until hurricane season is over.”
• “In defense of our boss, I don’t think it’s unreasonable to err on the side of caution right now. There are times to take risks and times to watch from the sidelines, and I think he’s making a prudent decision given the economic climate.”
• “The principal knew that the phoned-in threat was likely just a student that didn’t want to go to class, but he decided to err on the side of caution and evacuate the school.”
• “I brought my life jacket in case we decided to go out on the boat. I know you said it’s too cold to hang out on the lake, but I figured I’d err on the side of caution.”

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