We are often asked why flashcards in our Japanese language learning system do not include every possible definition of a particular word.
For example, for the word 会う (あう) why do we use "to meet", instead of "to meet; to encounter; to have an accident; to have a bad experience" as used in the EDICT dictionary?
The answer lies in the purpose of Cooori's system. The online language learning flashcards are not necessarily meant to teach every possible meaning and use of a particular word, but rather to give a strong starting point for using the word. Trying to teach every possible definition, both common and obscure, from the very beginning would only make it hard since you will try to force yourself to memorize every little detail. Allowing you to make the connections between definitions yourself, rather than presenting all possible definitions, avoids redundancy that could clutter the associations with other words in your brain.
In the case of 会う, we feel that "to encounter" can be derived from "to meet". We think that making that connection yourself makes the imprint of the word stronger than if we had told you to memorize both definitions from the start.
We also strive to make every one of our flashcard word definitions unique. In other words, every word must have a definition that is unique to it. Once again, this is to reduce confusion in your brain, and to make it easier to recall words when the system asks you for the word making remembering words, and therefore language learning, extremely efficient.
In a system that doesn't have unique definitions when a student is shown an English definition of a word and asked to identify its Japanese equivalent it is possible to have multiple "right" answers which can confuse the student. For example, in a system where 友達 tomodachi, 友人 yuujin, 親友 shinyuu and 仲良し nakayoshi are all defined as "friend," if a student is given the definition "friend" the student will not be able to know which Japanese word the system wants him/her to identify. In Cooori, the online language learning system, a user would be asked to give the Japanese word for "friend", and the user would be able to answer tomodachi because yuujin (friend (formal)), shinyuu (close friend) and nakayoshi (good friend; buddy) all have unique definitions.
This approach may be confusing for users that have already made connections through other learning methods. However, once you get used to it we know that it will make remembering much easier.