porphyraceous, a. ? Obs. rare.
(pɔːfɪˈreɪʃəs)
[f. porphyr- + -aceous.]
Of the nature of or allied to porphyry; porphyritic.
| 1799 Kirwan Geol. Ess. 207 Charpentier mentions a sort of stone which he calls porphyraceous, though he does not ascribe felspar to it. Hence 1828 in Webster; and in mod. Dicts. |