One of the first things new copy editors learn is that they should change the contraction 'til to the word till, or, in more formal contexts, until.

Then, if they're anything like me, they spend the next couple years running around telling everyone who'll suffer their company that the form with one L and the apostrophe is wrong, wrong, wrong. It takes no apostrophe and two Ls. End of story.

Eventually, the inevitable occurs: Someone, perhaps an editor who's been around the block a few times, points out that the rules of contractions mean that you certainly can use 'til if you want to. Though it's probably not a good idea. Because pros opt for till, the only people using ‘til are likely to be amateurs, which puts a serious blemish on 'til's image that can stain the image of any writer who uses it.

But in all my years of dealing with till and its cousins, there's a little fact I never came across — that is, till I brought this subject up in a recent column. A few weeks ago, I mentioned that one of my summer beach reads contained an error: the word 'til in place of till. It had one L, but no apostrophe. So it was neither the official word nor a contraction of until.

Soon after, I got an email from Warren in Albany who told me something I did not know: Merriam-Webster's Collegiate dictionary allows 'til as a synonym of till. And it appears Merriam-Webster isn't alone. Webster's New World College online dictionary agrees.

Does that let the editor of the book off the hook? Not exactly. Most books are edited according to the Chicago Manual of Style, which is pretty clear on the matter. “till. This is a perfectly good preposition and conjunction. It is not a contraction of ‘until' and should not be written 'til,” the Chicago Manual explains.

The word till actually predates until. Back before no one had yet uttered, “I can wait until tomorrow” it was proper to say “I can wait till tomorrow.”

Also, just because a dictionary gives you multiple options doesn't mean that they're equally good. On the contrary, dictionaries indicate their preferred or standard forms, usually by showing them first then listing alternate or “variant” forms after them. For every dictionary I've ever checked, the preference is clear: till is the way to go.

Of course, book copy editors don't have to do what the Chicago manual says, or even what the dictionary and grammar books say. If they did, Cormac McCarthy's writing would have a lot more apostrophes.

In many publishing houses, it's customary to create a custom “style sheet” for every manuscript. These are just like mini style guides that document special rules for the whole book. For example, the style sheet for McCarthy's “The Road” probably contained an entry like: “contractions: no apostrophes.”

So there's no reason a novel couldn't have its own rule: “til: one L, no apostrophe.” But these kinds of weird style choices usually occur only when a copy editor or writer has a good reason to buck convention and use a form that most of their colleagues consider an outright error.

What does all this mean to you? You can, technically, use any form of till that you like. But if you want one editor's advice, I say write it till. Or, if you want to steer clear of the whole hornet's nest, you can always use until instead.

JUNE CASAGRANDE is the author of “It Was the Best of Sentences, It Was the Worst of Sentences.” She can be reached at JuneTCN@aol.com.