A dictionary entry answers two questions, and most people only read one of them. The definition tells you what a word means. The usage label, in small italics before it, tells you whether you can say it. Skip the label and you end up with a word that is technically correct and socially wrong.
The label is doing more work than the definition
Here is the shape of the problem. Two words can share a definition almost exactly and be completely different tools.
Take a word marked informal and a word marked formal with the same gloss. The dictionary is not being fussy by separating them. It is telling you that one of them will sound odd in an email to a professor and the other will sound odd in a message to a friend, and that no amount of knowing the meaning will save you from choosing wrong.
This matters more for learners than for native speakers, who mostly absorb register by exposure without ever naming it. If your English comes from textbooks and exam prep, your intake is skewed hard toward one end of the range, and the labels are the only thing in the dictionary that tells you so.
Formal and informal, the two you half-know
These are the labels people do read, and they are still worth being precise about.
Cambridge describes formal language as used in serious or official contexts, or when trying to impress, and notes it would not be appropriate in ordinary conversation. Informal is the mirror: ordinary speech and writing, used between friends or in relaxed situations, not appropriate for formal ones.
The word “appropriate” is carrying the weight. It is not that informal words are lesser. It is that both labels describe a fit between a word and a situation, and both directions of mismatch are real errors.
Over-formal English is the more common learner failure and the less commonly corrected one, because nobody wants to tell you that your very careful sentence sounds strange. It is also self-reinforcing: the formal word was the one the textbook taught, it was the one the exam rewarded, and nothing in that pipeline ever signalled that it had a range.
The test I use on my own writing is small. Read the sentence out loud as if speaking to the actual reader. If a word makes you feel like you are performing, it is probably sitting one register too high for the situation, and the dictionary told you so in italics before you ever used it.
Three different kinds of old
This is where the labels stop being intuitive, and where they are most useful. Dictionary.com draws the lines by date.
| Label | What it means | Where you meet it |
|---|---|---|
| dated / old-fashioned | no longer in common modern use | older speakers, older writing |
| archaic | common until around 1900, now used only for deliberate old-sounding effect | historical fiction, jokes, poetry |
| obsolete | not widely used since at least 1750 | texts from before 1750 |
| rare | not obsolete or archaic, just seldom used | anywhere, infrequently |
The practical difference: a dated word will make you sound like someone’s grandfather, which is sometimes charming. An archaic word will make you sound like you are doing a bit. An obsolete word will simply not be understood. These are three different social outcomes and one label away from each other.
Disparaging and offensive are not the same label
This pair is the most useful distinction in the whole system and the one almost nobody knows.
Dictionary.com defines disparaging as used with the intention of belittling or insulting someone, even though the listener may not actually take it that way. Offensive is defined the other way round: perceived as belittling or insulting by the person who hears it, regardless of whether the speaker intended that.
So one label is about the speaker and the other is about the listener. A word can be marked offensive without anyone meaning harm by it, which is exactly the case a learner needs warning about, because good intentions do not disarm it. If you are ever going to obey one label without argument, make it this one.
Literary, humorous, ironic
These backfire in a way the others do not, because using them wrong does not sound like a mistake. It sounds like a choice.
Dictionary.com describes literary words as ones not commonly used in speech or writing except when someone is deliberately trying to sound poetic or old-bookish. Drop one into a work email and the reader does not think “non-native speaker”. They think you were being grand on purpose.
The same applies to labels like humorous and ironic. They tell you the word carries a wink. Deliver a wink you did not mean and the sentence still parses; it just says something about you that you did not intend to say.
The labels are easy to miss on purpose
Dictionaries put them in small italics, often abbreviated, sometimes tucked after the part of speech and before the definition where your eye is already moving past.
- Look for a short italic tag immediately before the definition text
- Check whether it applies to the whole entry or to one numbered sense, which is common and easy to misread
- Watch for regional tags like “chiefly British” or “North American”, which are labels too
- Note that different dictionaries use different sets, so “dated” in one is “old-fashioned” in another
The second item on that list is the one that actually bites. Labels frequently attach to a single numbered sense rather than the whole entry, and the senses are stacked in one block. A word can be entirely neutral in sense 1, informal in sense 2, and offensive in sense 4, with nothing but a small tag distinguishing them. Read the label attached to the sense you want, not the first label you see on the page.
If you are the kind of person who looks a word up and reads only the first line, that first line is often exactly where the label is not.
Labels about place and field, not tone
Two more families get lumped in with the register labels and behave differently.
Regional tags like “chiefly British”, “North American” or “Australian” are not warnings about formality at all. They tell you which readers will find the word ordinary. The failure they prevent is subtler than sounding rude: it is sounding like you learned English from four countries at once, which is exactly what happens when your input is textbooks from one place and streaming from another.
Field labels do something else again. A word marked law, medicine or computing is fully standard inside that field and can be genuinely opaque outside it. “Consideration” in a contract does not mean thoughtfulness. Nothing about the word looks specialised, and the label is the only signal that you have wandered into a place where the ordinary meaning does not apply.
Both kinds are easy to skip because neither sounds like a prohibition. They are closer to a map than a warning.
When a word has no label at all
No label means neutral, which is not the same as universally safe.
Labels cover register and attitude. They do not tell you which words the word likes to sit beside, how common it is, or whether it is the right choice among four near-synonyms that all look unlabelled. That is a different problem, and it is the one behind most “grammatically correct but nobody says that” sentences. We went through part of it in why translations and definitions are not interchangeable, and the near-synonym half shows up in commonly confused words.
There is also a frequency problem hiding here. Dictionaries list senses that are attested, not senses that are common, and rarity does not always earn a label. A sense can be perfectly current, perfectly unlabelled, and still something you will encounter once a decade. The entry does not rank them by how likely you are to need them.
It is worth naming the labels that do not exist, because their absence is where most of my own mistakes have come from. There is no tag for “common in writing, almost never said out loud”, which describes a large slice of exam vocabulary. There is no tag for “learners overuse this”, though anyone who has marked essays could list twenty. And there is no tag for “correct but slightly try-hard”, which is the single most common thing wrong with an advanced learner’s sentence.
Those gaps are not oversights. A dictionary describes the language; it does not describe you, and it has no way of knowing that a word is fine for everyone except the person most likely to look it up.
The general fix is the boring one: see the word in real sentences, more than once, until the company it keeps is part of what you know about it. Labels tell you where a word is allowed. Examples tell you where it actually lives, and the second question is the one you are really asking.
How Vocaby handles this
Every one of the 29,000+ words in Vocaby ships with its IPA, native audio and an example sentence, which is the part that carries what a bare definition cannot. A single example will not tell you a word is disparaging, but it does show you the register the word actually lives in, and that is most of what the labels are pointing at.
FSRS spaced repetition then brings the word back before you lose it. Register is especially easy to lose, because it is the part you learned last and the part you never get corrected on. You can see how an individual entry is laid out on any of the word pages.
Read the label before the definition. It is shorter, and it is the half that decides whether the word is usable.
Get Vocaby on the App StoreFrequently asked questions
- What is a usage label in a dictionary?
- A short tag placed before or after a definition that describes how a word is used rather than what it means: informal, formal, dated, literary, slang, offensive, and so on. The definition tells you the meaning; the label tells you the situations where using it will not go wrong.
- What is the difference between archaic and obsolete?
- They mark different depths of old. Dictionary.com defines obsolete as not widely used since at least 1750, so you meet it only in older texts. Archaic means the word was common until roughly 1900 and now appears only when someone is deliberately reaching for an old-sounding word.
- If a word has no label, is it always safe?
- Usually, but no label means neutral rather than universally appropriate. Labels catch register and attitude; they do not catch collocation, frequency, or the fact that a technically correct word can still be the wrong one. Seeing the word in real sentences is what covers the rest.
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