1. relating to or containing phenocrysts (large crystals embedded in a finer-grained matrix in igneous rock)
Usage: geological

Examples

• The phenocrystic texture of the volcanic rock was clearly visible under the microscope.
• Geologists identified several phenocrystic minerals in the lava sample.
• The phenocrystic feldspar crystals stood out against the fine-grained groundmass.
• This phenocrystic basalt contains large olivine crystals.
• The rock’s phenocrystic nature indicates it cooled slowly at first, then rapidly.