Wiktionary
irreplaceably
adv. In an irreplaceable manner; (context frequently English) uniquely, singularly.
Usage examples of "irreplaceably".
So what remained of the treasures we had brought—even those huge and irreplaceably beautiful gold and silver disks which had served Motecuzóma for gongs—became only solid ingots of gold and silver as featureless and unlovely as adobe bricks.
It would consume the host, particularly its brain, where brain cells died irreplaceably in a great progression.
This was accurate enough, since it is the only act which can irreplaceably destroy a unit of society.