I know we’ve already had a couple of discussions regarding hyphenation, especially hyphenating compound phrases, but there is still more to discuss: When should two become one?
If you check Merriam-Webster’s Collegiate Dictionary (11th ed), you will find long-standing with no recognition of longstanding. The American Heritage Dictionary of the English Language (5th ed) gives you long-standing or longstanding, with the hyphenated version preferred. The New York Times uses longstanding. The style manuals, such as Chicago (16th ed), tell you to closeup prefixes such as post, pre, and anti, even when a double letter occurs.
What no one seems to tell us is when two should become one.
I have come to the conclusion that the test is whether the combined form can be viewed as a single word; that is, we hyphenate the phrase when the phrase can have meaning that is different from that of the single word form or when creating a single word is illogical on its face.
A good example of the test is the phrase small animal practice. First, in the absence of the hyphen we know the phrase can mean either a practice that deals with small animals or a small practice that deals with animals. When we add the hyphen so that it becomes small-animal practice, we know it means a practice that deals with small animals. But it would be illogical to make the phrase smallanimal practice a single word because the single word smallanimal has no meaning in English; each word has to stand on its own and can be combined only with a hyphen to be logical within the constraints of English.
Contrast small animal practice with long-standing practice. In the latter case, long-standing and longstanding are both meaningful and logical. In addition, each can stand on its own as a “word.” This, I think, is the logic behind closing up certain prefixes and suffixes rather than hyphenating them.
Certainly, as can be discerned from the examples above, there can be no confusion when long-standing becomes longstanding, but that is not true of small animal practice, which brings us back to the ultimate rule of making writing smoothly understandable without loss of precision of meaning.
Interestingly, Bryan Garner, in Garner’s Modern American Usage (2009), simply states for the entry long-standing “adj. So spelled (with the hyphen).” That’s the complete discussion. No explanation why we must use the hyphen nor recognition of the trend to do away with the hyphen.
I suppose that the argument can fairly be made that long-lived and long-range are hyphenated adjectives so why make an exception of long-standing? Conversely, one could ask why these two phrases cannot also be seen as single words and thus should be joined rather than hyphenated.
I admit I’m torn. I vacillate between long-standing and longstanding, but only consider long-range and long-lived. Invariably I end up with long-standing, but I do want to be able to justify my use of longstanding for those projects when I (or the author) do use the single form. The only sufficient justification I can give is that the meaning and readability are the same in both forms.
Spelling and grammar need to be viewed with the same lens and focus: What matters is readability and clarity of meaning; all else pales in importance. If the test is met, then what does the addition or subtraction of a hyphen matter? In the case of a compound adjective as in small animal practice, there are differences in both meaning and readability between small animal practice, small-animal practice, and smallanimal practice. In the case of longstanding, there is no difference between longstanding and long-standing, but long standing does have different meaning and readability characteristics.
The professional editor needs to make a decision on when two becomes one and be able to support that decision. English changes and we need to change with it, but we also need to understand why the change occurs and be able to justify it by applying the rules of meaning and readability.