I believe this word originates from "Deolali" which is a former site of a British Army transit camp in India where soldiers were sent to recuperate if they were considered to be under traumatic stress as it's know today.
High grademarijuana or marijuana laced with cocaine. Referenced in the Master P song Bourbans and 'Llacs off of the Album Ghetto D.
This is for the Burbans and the Cadillac's
With the tens and twelves bumpin in the back This is for the players smokin doolamac
Slappin skins, makin dividends and riding strapped