The word 'yill' comes from the origins of the word chill, and is the coolest of all chills. This occurs when the coolest of all your hommies chill together and ingage in activities such as, smoke, drink, play video games, pull missions, and fool with tha girls.
"Yo G, you wanna yill tonight? i got a 6 pack and 3 bitches ready to go"
Can also be used in the context of "Yo hommie, are we yilling tonight?"
"First guy: Yo man, I'm sorry, I drank your beer by accident. Next guy: No worries, its yills."