The -og Family: Catalog, Dialog (US)

American English trims a silent ending off a small group of words: catalog, analog, dialog. Where British English writes -ogue, US spelling can stop at -og — you write it the way you say it, "cat-a-log," with no silent letters on the end. But this is the one UK/US pattern that isn't total, so it's worth knowing exactly which words shorten and which don't.

The pattern

US spelling drops the silent -ue on these:

• catalog, analog, dialog (especially the computing term, a "dialog box")

What you hear is what you write. If you're writing American English, catalog and analog are the standard short forms.

The important twist: it's only half the family

Here's what makes this pattern different from color or center, where every word flips. American English kept the full spelling for some of these words:

• dialogue and monologue are usually still written in full, even in the US, in ordinary writing (stories, essays, scripts).
• catalog and analog are the ones that clearly shorten.
• prologue, epilogue, travelogue also normally keep the full -ogue in the US.

So the safe US rule is narrower than you'd expect: shorten catalog and analog, but don't assume every -ogue word loses its tail. When unsure, dialogue spelled in full is never wrong in America.

The computing exception

There's one place -og is firmly standard everywhere, even in British tech writing: the computer term dialog box (the little pop-up window). Software has used dialog for decades, so a "dialog box" keeps the short spelling on both sides of the Atlantic — while a conversation in a story is still a dialogue. Same root word, two spellings, depending on whether you mean the pop-up or the talking.

Watch out — don't over-shorten

Because the pattern is incomplete, the mistake in US writing is over-applying it — chopping the -ue off words that keep it. Don't shorten monologue to monolog or epilogue to epilog in an essay; those look wrong. Stick to the two reliable short forms — catalog, analog — and leave the storytelling words in full.

A 30-second proofreading pass

When you finish a piece, glance through for this small family. Try fixing this line:

"The store's catalogue is online, and the movie's opening monolog runs for a full minute."

Catalogue should shorten to US catalog, and monolog should go back to the full monologue — the mistake ran in both directions. For US writing: catalog… monologue. A quick look sorts it, because there are only ever a few of these words about.

Quick check

Give the usual US spelling:

1. Browse the online cat___.

2. An old-style, non-digital signal is an anal___ one.

3. A pop-up box on a computer is a dial___ box.

4. The novel opens with a character's long ___ (a single-speaker speech).

Where the short forms come from

The words that did shorten in America — catalog, analog — are the everyday, practical ones: a shop's catalog, an analog clock or signal. It's often the words used most in business and technology that got trimmed first, because people wrote them constantly and the silent letters felt like wasted effort. The more literary words — dialogue, monologue, prologue — stayed full because they live in stories and scripts, where the traditional spelling still feels right. That's a rough pattern, not a strict rule, but it explains why the family split the way it did.

Words that never shorten anywhere

A few -ogue words keep their full spelling in both countries because they come straight from Greek and were never trimmed: synagogue (a place of worship), demagogue (a leader who whips up a crowd), pedagogue (an old word for a teacher). You won't reach for these often, but they're a good reminder that -ogue is the original ending and -og is the special American short form of just a couple of common words. If a word feels formal or old, spell it -ogue.

The bigger picture: silent letters

The silent -ue is one example of something English is full of — letters we write but don't say, like the k in knee, the b in doubt, or the gh in night. American spelling has trimmed a few of these (catalog, analog) but left most alone, which is why English still looks the way it does. The skill for all of them is the same: you can't trust your ear, so you learn the word by sight and check it when you proofread. And the good news for US writing is that you only ever have to remove letters from two words here — catalog and analog — while leaving everything else exactly as it looks in the dictionary.

Watch out — the mistake runs both ways

Because only some of these words shorten in American English, you can slip in two opposite directions — chopping off a tail that ought to stay, or keeping one that should go:

• ✗ the opening monolog ran for a minute → ✓ the opening monologue (keep the tail)
• ✗ browse our online catalogue → ✓ browse our online catalog (drop the tail)

The safe habit is to shorten only the two everyday, practical words — catalog and analog — and to leave the storytelling words (monologue, prologue, epilogue, travelogue) in full. When you're genuinely unsure which way a word goes, remember that a full -ogue spelling is never actually wrong in American writing, so the longer form is always the safer guess. Over-shortening, on the other hand, is what looks like a real mistake.

Where next

• Catalogue or Catalog? UK vs US — the two spellings side by side.
• The -or Family: Color, Favor, Honor — another US spelling pattern.
• Spelling Strategies That Work — remembering which words shorten.