# What is the proper way to abrevieate "purchase orders"? **URL:** \ **Category:** Factual Questions\ **Created:** [March 7, 2007, 1:26am UTC](https://boards.straightdope.com/t/what-is-the-proper-way-to-abrevieate-purchase-orders/394894 "2007-03-07T01:26:23Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![Blunt](https://avatars.discourse-cdn.com/v4/letter/b/ccd318/32.png) [@Blunt](https://boards.straightdope.com/u/Blunt)\ **Post date:** [March 7, 2007, 1:26am UTC](https://boards.straightdope.com/t/what-is-the-proper-way-to-abrevieate-purchase-orders/394894/1 "2007-03-07T01:26:23Z")
At work I deal with purchase orders a lot, and refer to them in emails all the time. Generally, the term PO is used instead of writing (or saying) the whole term “purchase order”. Now, this is probably a dumb question, but how should I type the plural of “PO”? I’ve seen a lot of people use “PO’s”, but of course the 's should really represent ownership and not plural. I’ve also seen people use “POS”, but that looks like something completely different to me, and “POs” looks strange to me as well. So, is there any _right_ way to spell this? The context of these emails is pretty informal, typically just questions shot between people or whatever. To be honest, the grammar/spelling isn’t always perfect in these emails, and I’m more just curious about this than actually worried about making a mistake. ---
**Author:** ![Shagnasty](https://avatars.discourse-cdn.com/v4/letter/s/9dc877/32.png) [@Shagnasty](https://boards.straightdope.com/u/Shagnasty)\ **Post date:** [March 7, 2007, 1:40am UTC](https://boards.straightdope.com/t/what-is-the-proper-way-to-abrevieate-purchase-orders/394894/2 "2007-03-07T01:40:04Z")
I used to work on a purchase order system with lots of big companies. It is PO and we always wrote PO’s as plural although I am not sure how correct that is formally speaking. ---
**Author:** ![Mbossa](https://avatars.discourse-cdn.com/v4/letter/m/73ab20/32.png) [@Mbossa](https://boards.straightdope.com/u/Mbossa)\ **Post date:** [March 7, 2007, 1:43am UTC](https://boards.straightdope.com/t/what-is-the-proper-way-to-abrevieate-purchase-orders/394894/3 "2007-03-07T01:43:25Z")
I don’t really see what’s wrong with “POs”. That’s what I’d use. But I do agree that “POS” (all caps) is bad and potentially misleading. ---
**Author:** ![Shagnasty](https://avatars.discourse-cdn.com/v4/letter/s/9dc877/32.png) [@Shagnasty](https://boards.straightdope.com/u/Shagnasty)\ **Post date:** [March 7, 2007, 1:48am UTC](https://boards.straightdope.com/t/what-is-the-proper-way-to-abrevieate-purchase-orders/394894/4 "2007-03-07T01:48:03Z")
POS is Point of Sale which is very different especially in a retail company. ---
**Author:** ![hermann](https://avatars.discourse-cdn.com/v4/letter/h/b487fb/32.png) [@hermann](https://boards.straightdope.com/u/hermann)\ **Post date:** [March 7, 2007, 1:59am UTC](https://boards.straightdope.com/t/what-is-the-proper-way-to-abrevieate-purchase-orders/394894/5 "2007-03-07T01:59:17Z")
I alway use “POs”. Oh, and I thought “POS” stood for “Piece of S\*\*\*” ---
**Author:** ![SmackFu](https://avatars.discourse-cdn.com/v4/letter/s/53a042/32.png) [@SmackFu](https://boards.straightdope.com/u/SmackFu)\ **Post date:** [March 7, 2007, 2:21am UTC](https://boards.straightdope.com/t/what-is-the-proper-way-to-abrevieate-purchase-orders/394894/6 "2007-03-07T02:21:16Z")
You think this is a headache… I’m currently working on some software that deals with POs and translating it is a pain. A lot of languages don’t use a shortened form so nothing fits. ---
**Author:** ![psycat90](https://avatars.discourse-cdn.com/v4/letter/p/7ea924/32.png) [@psycat90](https://boards.straightdope.com/u/psycat90)\ **Post date:** [March 7, 2007, 2:54am UTC](https://boards.straightdope.com/t/what-is-the-proper-way-to-abrevieate-purchase-orders/394894/7 "2007-03-07T02:54:42Z")
I’m in the same boat at work. I use POs for purchase orders. POS is Point of Sale, which is also used within our company. ---
**Author:** ![Scarlett67](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/scarlett67/32/7387_2.png) [@Scarlett67](https://boards.straightdope.com/u/Scarlett67)\ **Post date:** [March 7, 2007, 3:20am UTC](https://boards.straightdope.com/t/what-is-the-proper-way-to-abrevieate-purchase-orders/394894/8 "2007-03-07T03:20:37Z")
The use of the apostrophe is a style choice; there is no concrete “right” or “wrong.” Use either POs or PO’s as you wish. However, “POS” would definitely be wrong. ---
**Author:** ![GiantRat](https://avatars.discourse-cdn.com/v4/letter/g/e47c2d/32.png) [@GiantRat](https://boards.straightdope.com/u/GiantRat)\ **Post date:** [March 7, 2007, 4:59am UTC](https://boards.straightdope.com/t/what-is-the-proper-way-to-abrevieate-purchase-orders/394894/9 "2007-03-07T04:59:33Z")
[QUOTE=Scarlett67] The use of the apostrophe is a style choice; there is no concrete “right” or “wrong.” Use either POs or PO’s as you wish. However, “POS” would definitely be wrong. [/QUOTE] The grammar Nazi in my shudders at this. The apostrophe implies either possession or contraction, and neither of those applies here. While pretty much everyone would get the drift, this is not at all grammatically correct. And they wonder why English is such a tough language to learn. . . :dubious: ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [March 7, 2007, 5:15am UTC](https://boards.straightdope.com/t/what-is-the-proper-way-to-abrevieate-purchase-orders/394894/10 "2007-03-07T05:15:44Z")
[QUOTE=GiantRat] The grammar Nazi in my shudders at this. The apostrophe implies either possession or contraction, and neither of those applies here. While pretty much everyone would get the drift, this is not at all grammatically correct. [/QUOTE] It’s not really a matter of grammar; it’s a matter of _spelling_. And **Scarlett67** has it right. Either one is right; just be consistent. According to the _Chicago Manual of Style_: > [@](#): > > Abbreviations with periods, lowercase letters used as nouns, and\*\* capital letters that would be confusing\*\* if \*s \*alone were added form the plural with an apostrophe and an _s_: > > M.A.'s and Ph.D.'s > x’s and y’s > S’s, A’s, I’s > SOS’s Bolding mine. The question is whether “POs” is felt to be confusing or not. Since POS is a frequent abbreviation in business contexts, probably in this case “PO’s” should be preferred. There is nothing incorrect about it. ---
**Author:** ![Scarlett67](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/scarlett67/32/7387_2.png) [@Scarlett67](https://boards.straightdope.com/u/Scarlett67)\ **Post date:** [March 7, 2007, 5:22am UTC](https://boards.straightdope.com/t/what-is-the-proper-way-to-abrevieate-purchase-orders/394894/11 "2007-03-07T05:22:39Z")
[QUOTE=GiantRat] The grammar Nazi in my shudders at this. The apostrophe implies either possession or contraction, and neither of those applies here. While pretty much everyone would get the drift, this is not at all grammatically correct. And they wonder why English is such a tough language to learn. . . :dubious: [/QUOTE] I’m not talking about adding the apostrophe anytime you want to make a plural. Some styles allow it when omitting it might cause confusion, such as the plural of a single letter, or the “do” in “do’s and don’ts” (which always looks weird no matter how you style it). I’d say “PO’s” falls into this category, and wouldn’t be uncomfortable styling it either way. (Though Chicago would lean toward omitting it, if an author preferred to keep it I would be OK with that.) On preview: **Colibri,** is that from the 14th or 15th edition? (I can’t be arsed to dig out my copy of 14.) 15 has only the examples of Ph.D.'s and M.A.'s and x’s and y’s at para. 7.16; it doesn’t mention general confusion (although Amy Einsohn’s _The Copyeditor’s Handbook_ [published before 15 came out] does). ---
**Author:** ![lissener](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lissener/32/6139_2.png) [@lissener](https://boards.straightdope.com/u/lissener)\ **Post date:** [March 7, 2007, 5:30am UTC](https://boards.straightdope.com/t/what-is-the-proper-way-to-abrevieate-purchase-orders/394894/12 "2007-03-07T05:30:38Z")
While I agree that the apostrophe should be eschewed unless it’s necessary to avoid confusion, the NYTimes uses such an apostrophe consistently. ---
**Author:** ![Mr.Slant](https://avatars.discourse-cdn.com/v4/letter/m/c57346/32.png) [@Mr.Slant](https://boards.straightdope.com/u/Mr.Slant)\ **Post date:** [March 7, 2007, 5:32am UTC](https://boards.straightdope.com/t/what-is-the-proper-way-to-abrevieate-purchase-orders/394894/13 "2007-03-07T05:32:11Z")
If your company is Enron, I suppose you should just spell it out and say “Probation Officers”. ---
**Author:** ![Gary\_T](https://avatars.discourse-cdn.com/v4/letter/g/3ec8ea/32.png) [@Gary\_T](https://boards.straightdope.com/u/Gary_T)\ **Post date:** [March 7, 2007, 5:49am UTC](https://boards.straightdope.com/t/what-is-the-proper-way-to-abrevieate-purchase-orders/394894/14 "2007-03-07T05:49:09Z")
[QUOTE=GiantRat] The grammar Nazi in my shudders at this. The apostrophe implies either possession or contraction… [/QUOTE] or the **plural for an abbreviation**. Maybe you missed that day, or maybe your schooling omitted it (since it doesn’t seem to be universal), but it’s a longstanding and fairly widespread practice. ---
**Author:** ![gazpacho](https://avatars.discourse-cdn.com/v4/letter/g/6f9a4e/32.png) [@gazpacho](https://boards.straightdope.com/u/gazpacho)\ **Post date:** [March 7, 2007, 6:13am UTC](https://boards.straightdope.com/t/what-is-the-proper-way-to-abrevieate-purchase-orders/394894/15 "2007-03-07T06:13:54Z")
[QUOTE=Gary T] or the **plural for an abbreviation**. Maybe you missed that day, or maybe your schooling omitted it (since it doesn’t seem to be universal), but it’s a longstanding and fairly widespread practice. [/QUOTE] Really? The plural of an abbreviation. I have never seen anything authoritative advocate that use of an apostrophe. Can you point me to a style guide that advocates this use? ---
**Author:** ![Gary\_T](https://avatars.discourse-cdn.com/v4/letter/g/3ec8ea/32.png) [@Gary\_T](https://boards.straightdope.com/u/Gary_T)\ **Post date:** [March 7, 2007, 6:32am UTC](https://boards.straightdope.com/t/what-is-the-proper-way-to-abrevieate-purchase-orders/394894/16 "2007-03-07T06:32:00Z")
[QUOTE=gazpacho] Really? The plural of an abbreviation. I have never seen anything authoritative advocate that use of an apostrophe. Can you point me to a style guide that advocates this use? [/QUOTE] Apparently the _Chicago Manual of Style_, as mentioned by **Colibri** in post #10, and whatever the _New York Times_ uses, as observed by **lissener** in post #12. ---
**Author:** ![Eleusis](https://avatars.discourse-cdn.com/v4/letter/e/f4b2a3/32.png) [@Eleusis](https://boards.straightdope.com/u/Eleusis)\ **Post date:** [March 7, 2007, 10:10am UTC](https://boards.straightdope.com/t/what-is-the-proper-way-to-abrevieate-purchase-orders/394894/17 "2007-03-07T10:10:43Z")
I say either “P.O.s” or “PO’s” The apostrophe could account for the contraction of “Order”. ---
**Author:** ![Gary\_T](https://avatars.discourse-cdn.com/v4/letter/g/3ec8ea/32.png) [@Gary\_T](https://boards.straightdope.com/u/Gary_T)\ **Post date:** [March 7, 2007, 3:53pm UTC](https://boards.straightdope.com/t/what-is-the-proper-way-to-abrevieate-purchase-orders/394894/18 "2007-03-07T15:53:31Z")
I think it’s safe to say the apostrophe indicates “this letter S is forming a plural, and is not part of the abbreviation.” As mentioned above, there is such a thing as a PO, and there is such a thing as a POS. Likewise, there is such thing as a TV, and there is such a thing as a TVS (thermal vacuum switch). Now, often the apostrophe is not truly necessary, either due to context (it’s extremely unlikely that someone dealing with televisions is also dealing with thermal vacuum switches) or upper/lower case usage (TVs is plural of TV, TVS is singular of TVS). But there might be cases where the apostrophe adds clarity. Then, of course, there’s the problem of possessives - “That TV’s picture is really clear.” Hence it’s not surprising that there isn’t universal and consistent application of either form. Which brings us back to the real, if less than totally satisfying answer: either way is acceptable, neither way is incorrect, but in certain specific cases one way might be clearer. ---
**Author:** ![Santo\_Rugger](https://avatars.discourse-cdn.com/v4/letter/s/e95f7d/32.png) [@Santo\_Rugger](https://boards.straightdope.com/u/Santo_Rugger)\ **Post date:** [March 7, 2007, 4:44pm UTC](https://boards.straightdope.com/t/what-is-the-proper-way-to-abrevieate-purchase-orders/394894/19 "2007-03-07T16:44:55Z")
FWIW, the standard at my work is to pluralize acronyms by adding a lower case “s”. So it would be POs, TVs, GRAs, etc. It’s a government job, so there’s a full page of explaination on the master acronym list, which is about 100 pages long. ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [March 7, 2007, 4:46pm UTC](https://boards.straightdope.com/t/what-is-the-proper-way-to-abrevieate-purchase-orders/394894/20 "2007-03-07T16:46:25Z")
[QUOTE=Scarlett67] I’d say “PO’s” falls into this category, and wouldn’t be uncomfortable styling it either way. (Though Chicago would lean toward omitting it, if an author preferred to keep it I would be OK with that.) On preview: **Colibri,** is that from the 14th or 15th edition? (I can’t be arsed to dig out my copy of 14.) 15 has only the examples of Ph.D.'s and M.A.'s and x’s and y’s at para. 7.16; it doesn’t mention general confusion (although Amy Einsohn’s _The Copyeditor’s Handbook_ [published before 15 came out] does). [/QUOTE] It’s the 13th Edition, actually, section 6.10, p. 160. I probably should update one of these decades. 🙂 However, I am not aware that the convention has changed significantly. I also would in general not use an apostrophe to make a plural UNLESS confusion is likely. In the previous section, 6.9 in my edition, Chicago indicates this is the preferred method for letters used as words, acronyms, etc. However, to prevent confusion, using an apostrophe is an accepted practice by major style manuals. (Certainly Chicago style, and I assume the NY Times uses either AP style or their own house style.) [QUOTE=Eleusis] I say either “P.O.s” or “PO’s” The apostrophe could account for the contraction of “Order”. [/QUOTE] Chicago style would make the first example “P.O.'s.” If you are using the apostrophe to indicate a contraction than the second example should be “P’O’s”; however, I have never seen that done and I doubt any style manual would accept it. To be clear: although an apostrophe is typically used to indicate a contraction or a possessive, those are not its only uses. It can also be used, quite correctly, to indicate other spelling conventions or for clarity. [Next page](https://boards.straightdope.com/t/what-is-the-proper-way-to-abrevieate-purchase-orders/394894.md?page=2)