How to link to word definitions
Let's say you are writing an article and you want to create a link to the definition of a word the understanding of which is crucial to understanding the article. But in this hypothetical situation, you don't want to link to the Wikipedia article for that word because it would be overkill. Wikipedia has a sister project that presents hundreds of thousands of definitions. It's called Wiktionary. Here's how you would provide a link to the definition of "understanding":
both [[wiktionary:understanding|]] and [[wikt:understanding|]] will look like this:
and link to the definition of the word "understanding".
Notice that the "pipe trick" (|) was used in the links above.
Read more: Help:Interwiki linking