Source : Webster's Revised Unabridged Dictionary (1913)

Grass tree \Grass" tree"\ (Bot.)
   (a) An Australian plant of the genus {Xanthorrh[oe]a}, having
       a thick trunk crowned with a dense tuft of pendulous,
       grasslike leaves, from the center of which arises a long
       stem, bearing at its summit a dense flower spike looking
       somewhat like a large cat-tail. These plants are often
       called ``blackboys'' from the large trunks denuded and
       blackened by fire. They yield two kinds of fragrant
       resin, called {Botany-bay gum}, and {Gum Acaroides}.
   (b) A similar Australian plant ({Kingia australis}).