Most dictionaries have two layers:
To understand a dictionary's definitions, you need to understand the words in the defining vocabulary. Since a typical learner's dictionary has a defining vocabulary containing 2000 or more words, you must already have at least an intermediate-level vocabulary to use the dictionary.
A multi-layer dictionary, like Learn These Words First, is different: The definitions are arranged in layers so they can be understood by learners with different levels of vocabulary:
Here is an example of a circular definition. The word easy is used to define difficult, and the word difficult is used to define easy:
Here is another example. If you do not already know any of these words (illness, sick, sickness), you will not get a helpful explanation of what they mean from these circular definitions:
Most dictionaries contain thousands of circular definitions like these, especially for the most basic words. This may not be a problem for someone who already has a large vocabulary, but circular definitions are frustrating for beginning-level learners.
The Learn These Words First dictionary is structured in a new way to eliminate circular definitions. The 360 words in the lessons are arranged in an order that allows each new word to be explained using only words that were explained earlier in the lessons. The rest of the words in the dictionary are defined using only the 360 words from the lessons. A computer program was used to check that the lessons and definitions contain no circular definitions.
The Learn These Words First dictionary is arranged in layers to eliminate circular definitions and make the dictionary accessible for beginning-level ESL students:
Many language courses teach vocabulary in topical lessons of about 30 words each (food, animals, clothing, colors, family, etc.). After learning 360 words in your first 12 lessons, you may understand words for about 12 topics, but the words you know will probably be inadequate for explaining most ideas outside of these limited topics.
Instead of arranging words by topic, the lesson vocabulary of Learn These Words First was carefully selected to maximize the explanatory power of your first 360 words: