It's a very common word and can be used in various contexts, similar to the English word "heart":
* Physical heart: Like "I have a problem with my dil."
* Emotional heart: Like "My dil is filled with joy."
* Love/affection: Like "He has a dil for her."
* Courage/bravery: Like "He has a big dil."
Let me know if you had another word in mind!