SG Heritage Dictionary

Porphyritic [\N] Webster's Dictionary 1828

1. PORPHYRIT'IC

2. POR'PHYRIZE, verb transitive To cause to resemble porphyry; to make spotted in its composition.

Porphyritic [Adjective] Webster's Dictionary 1913

Relating to, or resembling, porphyry, that is, characterized by the presence of distinct crystals, as of feldspar, quartz, or augite, in a relatively fine-grained base, often aphanitic or cryptocrystalline.