Perhaps even more than other grammatical errors, this little pet peeve annoys me to no end. Even so, I see it more and more every day. It seems like simple enough a concept, but many people make this increasingly common error. Is it wrong to say PIN number? Yes. Allow me to explain why.
Whether you’re talking about the passcode associated with your debit card or the number that is linked to any number of other kinds of accounts, a PIN is a personal identification number. It’s an acronym that has become an accepted word of its own. When we see PIN in print, we are more likely to say “pin” than we are to say the individual letters “pee-eye-enn.” That much is fine and perfectly acceptable.
However, by referring to the series of digits as a PIN number, you are being completely and utterly redundant. PIN stands for “personal identification number” and, as such, PIN number would then expand to “personal identification number number.” That’s pretty silly, right? Then why does the official website of the Vancouver Public Library even make this mistake?
The same concept applies to other related acronyms like SIN (social insurance number), SSN (social security number), and TIN (taxpayer identification number). You should never say SIN number or SSN number, because you would be making the same mistake as you would saying SIN number. It’s not a matter of writing style; it’s just grammatically incorrect.
Granted, some redundancy is good under certain circumstances, but the redundancy of PIN number is simply unacceptable. Whenever you use any kind of acronym, try replacing the acronym with the full words to ensure that your sentence still makes grammatical sense.
Do you have a suggestion for a future Grammar 101 post? Let me know through the comment form below.
My other favorites include “ATM Machine” and “HIV Virus”
Maybe you can call your site “BTR Rhetoric”?
“you are being completely and utterly redundant.”, this sentence sounds like what Simon Cowell would utter in his critque as a judge on American Idol.
Sorry I digress but it’s good of you to point out the redundancy of using acronym that make the sentence grammatically incorrect.
On the other hand the acronyms have become just letters because of their overuse making the addition of the word “virus” after HIV and “number” after PIN just part of the lexicon.
I think the redundancy also serves as an identifier. When someone asks verbally for your PIN, are they asking for your PIN, your pin or even your pen? Asking for a PIN number, while it may be redundant, makes it clear what you are seeking.
And, it seems only certain acronyms carry such redundancies. For example, I don’t think I’ve ever heard any speak of an “ATV vehicle,” just an ATV.