Weed Wacker Share definition Flag Someone who smokes marijuana and masturbates, often at the same time. Scott: Today i met this guy in rehab. He told me about that he's addicted to pot and jacking off.Eli: Oh, so he's a Weed Wacker? Weed Wacker by TheBigSTD August 11, 2010 Get the Weed Wacker mug.