Dro

From Rap Dictionary

noun

dro

Short for hydro, marijuana that is grown hydroponically, i.e. without the use of soil, just nutrified water. Weed grown in this fashion is usually of a much higher quality than normal. First introduced to us by Bone Thugs N Harmony. "Shorty wanna ride wit me (ride wit me) we can get low Hop into the Chevy fo' do', blow dro" -- Young Buck (Shorty Wanna Ride) [1]