It is very simple, it's like making a link to some special terms such as Bank or LEO or anything that have a definition in LeoGlossay menu.
You can find all links here https://leofinance.io/@leoglossary/leoglossary-main-menu
Suppose your article contains word "Blockchain", you just have to add a link to that word you normally do by clicking chain icon add a word and then submit it as a clickable word with a link to LeoGlossary.
Simple code in Markdown is
[Blockchain](https://leofinance.io/@leoglossary/blockchain)
In your article it will appear like this as below:
Posted Using LeoFinance Beta