musquash poisonn.rare = musquash rootn. (a).Apparently only attested in dictionaries or glossaries.
ΚΠ
1897 N. L. Britton & A. BrownIllustr. Flora Northern U.S. II. 536Cicuta maculata... Musquash Root... Poisonous. Called also Spotted Cowbane, and Beaver-poison.]
1908 N.E.D. at MusquashMusquash poison, the plant Cicuta maculata (Britton & Brown American Flora).