There are two kinds of English-English dictionaries: dictionaries for learners and dictionaries for native speakers. Dictionaries for native speakers are used by Americans, Britons, etc. to look up very difficult words, such as tintinnabulation. Dictionaries for learners are used by people who are learning English as a second language.
Dictionaries for native speakers usually have more words than dictionaries for learners, but the definitions are complicated, and there are fewer example sentences. Therefore your first dictionary should be a dictionary for learners. Later, you will need other dictionaries — for example, a dictionary of phrasal verbs and a big dictionary for native speakers.
If possible, get a software dictionary instead of a paper one. Here are some reasons why:
Quick searching. Software dictionaries let you look up words very quickly. Typing a word on your keyboard is much, much faster than turning pages in a large, heavy book.
Easy copying. If you're making your own SuperMemo collection for learning English, you can select whole sentences and definitions in the dictionary, and copy them to your new items.
Recordings. In many software dictionaries, you can listen to recordings which show you how to pronounce a word. Recordings cannot replace phonetic transcriptions (see below), but they are certainly a useful feature.
More information/clearer layout. Paper dictionaries have limited space, which is why they are printed in a small font and the layout is very crowded. A computer dictionary has more space, so it can give more information (e.g. more example sentences) or it can present the same information in a clearer way (bigger font, blank lines, etc.).
Why is quick searching so important? Because if you want to learn English well, you should look up lots of words, and a paper dictionary discourages you from that. You want to look up a word, you look at the huge book with 1500 pages, think "Ah, never mind", and you never learn that word. With a software dictionary, once you see how easy it is, you will start looking up hundreds of words every week. And your English will get a huge boost.
Note: The advice in this article applies to both book dictionaries and to software dictionaries. However, the quality of a software dictionary also depends on other features (e.g. ease-of-use, software speed), which are not discussed here.
Phonetic transcription for every word
Standards of transcription
A good dictionary must give phonetic transcription for every word. Phonetic transcription tells you how to pronounce a word. Ideally, the transcription should be based on the International Phonetic Alphabet (IPA), which is the standard phonetic alphabet used by linguists all over the world. Here is what IPA-based phonetic transcription looks like:
Generally, dictionaries from UK publishers (Cambridge, Collins, Longman, Oxford) use IPA-based transcriptions, while dictionaries published in the USA (Random House, Merriam-Webster, etc.) use their own systems. Some dictionaries give phonetic transcription only for "the most difficult words" (usually less than 5% of all words). These are almost useless to learners, because all English words are difficult if you are not a native speaker. Avoid them.
Phonetic transcriptions vs. recordings
Virtually all software dictionaries nowadays have audio recordings. If you can listen to a native speaker pronouncing a word, do you still need written pronunciations? Yes, for four reasons:
Your ears are not perfect. Even if the dictionary has high-quality recordings, it is always good to see all the sounds in a word. Sometimes you hear a "t"; then somebody tells you it should be a "d", and then you start hearing a "d".
Recordings are never perfect. No matter how high the quality of recordings, there are always some bad ones. For example, here is the recording for the word back from the Collins COBUILD Advanced Learner's Dictionary. Not very clear, is it? Phonetic transcription (/
/) is always clear, because it represents each English sound with a different symbol.
Dictionaries often have more transcriptions than recordings. For example, the transcriptions may show two ways to pronounce a word, but the recording will show only one. Or a dictionary may have British and American transcriptions, but only British recordings.
Reading a transcription is faster than clicking a button and listening to a recording.
Example sentences for every word
A good dictionary must give example sentences for every word. Example sentences are English sentences which contain the word. Some dictionaries give them after the definition of a word. Example sentences are marked in yellow in this picture:
[Longman Dictionary of English Language and Culture]
Example sentences are not just helpful — they are actually more important than definitions. While a definition tells you the meaning of a word and (sometimes) gives you some grammatical information, example sentences have at least three advantages:
They let you check if you've understood the definition correctly. The meaning of a word can become much clearer if you read a few sentences with the word.
They show you how to use a word in sentences. Many words "go with" certain grammar structures (e.g. important is often used in the phrase "It is important to...") or words (e.g. weather goes with forecast and not e.g. prediction). Example sentences present this information in a clear way. You can easily imitate them to make your own natural sentences.
They program your brain to produce correct English sentences. If you read an English sentence, there is a good chance that it will stay in your head, and that you will be able to build a similar sentence (or part of a sentence) to express your thoughts another day. So the more English sentences you read, the more you can produce.