Definition of "doob"

Doob is a shallow rooted plant and obtains its food from the surface layer of soil; most of the other grasses, with which it has to compete, such as motha (Cyperus rotundus), dabhi (Imperata arundinacea) and rari (Saccharum spontaneum) are comparatively deep-rooted; […]

1911, C.M. Hutchinson, “Turf”, in Agricultural Journal Of India, Pusa: Agricultural Research Institute, page 368

I don't smoke doobs and I don't really hang out.

1996, Eric Bogosian, SubUrbia (motion picture), spoken by Bee-Bee (Dina Spybey-Waters)