not capable of being broken or separated into parts

Pronunciation:
in-FRAN-jih-bul

In a sentence:
Lisa’s infrangible ethical resolve was the envy of all the younger girls in her community—all of whom wanted to be like Lisa, talk like Lisa, and unashamedly drink bourbon like Lisa.

In a different sentence:
The infrangible bond that Steven had forged with his stepmother made both Steven’s mother and father extremely jealous and resentful.