What is "irreplacable"

Usage examples of "irreplacable".

Shatter the irreplacable mechanical and human gears that allowed the empire to function?

Before rescue forces from other quadrangles brought the situation into hand, a third of the buildings in the target area were more or less destroyed (including an irreplacable collection of seventeen hundred illustrated manuscripts from the pre-Kamakura period), half at least of the students and faculty were dead or dying, and all but a handful were fit only for custodial asylums.

Whatever their reaction over the loss of one of their irreplacable submarine craft, Efrel had succeeded in maintaining their support in the rebellion.