noun
cubic crystal system
Geology and crystallography term for one of the seven crystal systems, where the unit cell is a cube.
岩塩は立方晶系に属する結晶構造を持つ。
Rock salt has a crystal structure belonging to the cubic crystal system.
結晶系 is the general term for 'crystal system'; 立方晶系 is one specific type.
Compound of 立方 (りっぽう, 'cube') + 晶系 (しょうけい, 'crystal system').