irreplaceable
Irreplaceable (adj) means So unique or valuable that nothing could take its place if lost. Example: “The stolen painting was irreplaceable, one of only three the artist ever made.”
How to use irreplaceable
Learner’s notesIn plain EnglishImpossible to replace because it's one of a kind.
Fill the gap
Can you complete this real example?
The stolen painting was _____, one of only three the artist ever made.
Etymology
Formed from ir- ("not") plus replaceable.