Subtartarean :: Subtangent (n.) The part of the axis contained between the ordinate and tangent drawn to the same point in a curve.
Tartareous :: Tartareous (a.) Of or pertaining to Tartarus; hellish.
Tartareous :: Tartareous (a.) Consisting of tartar; of the nature of tartar.
Tartareous :: Tartareous (a.) Having the surface rough and crumbling; as, many lichens are tartareous..