n. [ Gr. &unr_; divided, divisible, fr. &unr_; to divide: cf. F. schiste. See Schism. ] (Geol.) Any crystalline rock having a foliated structure (see Foliation) and hence admitting of ready division into slabs or slates. The common kinds are mica schist, and hornblendic schist, consisting chiefly of quartz with mica or hornblende and often feldspar. [ 1913 Webster ]
a. Of a slate color. [ 1913 Webster ]
a. Schistose. [ 1913 Webster ]
n. [ Cf. F. schistosité. ] (Geol.) The quality or state of being schistose. [ 1913 Webster ]