Tartareous
Pronunciation : Tar*ta"re*ous
Part of Speech : a.
Etymology : [Cf. 1st Tartarous.]
Definition : 1. Consisting of tartar; of the nature of tartar.
2. (Bot.)
Defn: Having the surface rough and crumbling; as, many lichens are tartareous.
Source : Webster's Unabridged Dictionary, 1913