Is It ‘One in the Same’ or ‘One and the Same’?

What Does “One and the Same” Mean?

The phrase ‘one and the same’ is an idiomatic expression used to emphasize that two or more things or people are identical or indistinguishable from one another. It often highlights that two separate entities are, in fact, the same thing or person. For example, the music artist Daniel Dumile is also known by the pseudonyms ‘MF Doom’ and ‘Viktor Vaughn.’ Since Daniel Dumile, ‘MF Doom,’ and ‘Viktor Vaughn’ all refer to the same person, they are “one and the same.”

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What Does “One in the Same” Mean?

Contrary to “one and the same,” “one in the same” is not a standard phrase in English. It’s a common mistake resulting from a misinterpretation of “one and the same.” The correct phrase to use when emphasizing identity or similarity is “one and the same.” For example, in a social media post discussing two similar products, someone might write, “These two smartphones are practically one in the same.” Here, the incorrect usage of “one in the same” fails to convey the intended meaning of identicalness. “One in the same” is a mondegreen and should be avoided when trying to showcase two things or people being the same.

Why Are They Used Incorrectly?

The confusion between “one and the same” and “one in the same” often arises due to the phonetic similarity between the two phrases. Additionally, people may hear the phrases used interchangeably and assume they mean the same thing. However, “one in the same” is grammatically incorrect and doesn’t convey the intended meaning of emphasizing identicalness.

How To Tell the Difference

To distinguish between “one and the same” and “one in the same,” remember that “one and the same” is the correct phrase to use when indicating that two or more things are identical or indistinguishable. On the other hand, “one in the same” is incorrect and should be avoided in formal writing or speech. A helpful tip is to break down the phrase and consider its individual components. “One and the same” suggests unity or identity between multiple elements, while “one in the same” doesn’t convey the same meaning and is grammatically incorrect.

Similar Language Misconceptions

The confusion between “one and the same” and “one in the same” is just one example of the many language misconceptions that exist. Here are a few more commonly confused phrases:

1. “Could of” vs. “Could have.” Often in informal writing, people mistakenly write “could of” instead of the correct “could have.” For example, “I could of gone to the party” should be “I could have gone to the party.”
2. “Irregardless” vs. “Regardless.” “Irregardless” is often used incorrectly in place of “regardless.” However, “irregardless” is considered nonstandard English, and “regardless” should be used instead. For instance, “Irregardless of the weather, we’re going to have a picnic” should be “Regardless of the weather, we’re going to have a picnic.”
3. “All intensive purposes” vs. “All intents and purposes.” This is an example of a mondegreen, where people mishear or misinterpret a phrase. The correct phrase is “all intents and purposes,” meaning “for all practical purposes.”

When trying to showcase multiple things or people are the same, make sure you use the idiomatic phrase “one and the same.” ‘One in the same’ is a common mistake and mondegreen that can be easily avoided. Make sure your expressions are used correctly to ensure your language and writing is understood. For more help with idioms and figurative language, learn more writing tips.