(Science: botany) a common weed with jointed stems (polygonum aviculare); knotweed.
The dog grass. See dog.
An infusion of polygonum aviculare was once supposed to have the effect of stopping the growth of an animal, and hence it was called, as by Shakespeare, hindering knotgrass. We want a boy extremely for this function, kept under for a year with milk and knotgrass. (Beau. & Fl)