irreplaceable

adj

1. (not-comparable)Incapable of being replaced, especially because of uniqueness or finiteness.

   “irreplaceable batteries”

   “irreplaceable family portrait”

   “irreplaceable team member”

   “For some purposes lead is unique and, apparently, irreplaceable. Battery plates may be an example of this.”

   “But whether or not the VCR makes a complete comeback, VHS enthusiasts agree that these tapes occupy an irreplaceable place in culture.”