noun
breccia
A geological term for a rock composed of angular fragments cemented together.
この崖は角礫岩でできている。
This cliff is made of breccia.
Compound of 角 (kaku, 'angle') + 礫 (reki, 'gravel') + 岩 (gan, 'rock'). The exact historical derivation is uncertain; the term is a modern geological coinage.