Single-word synonym for "immensely valuable"?

synonyms

Solution 1:

The word "invaluable" is what you're looking for I think. Definition: beyond calculable or appraisable value.

Solution 2:

To quote the well-know credit card ad: priceless.

Solution 3:

There are also the terms precious, which means "of great price; costly; having a high money-value; of great worth; held in high esteem; intrinsically valuable," and inestimable, which means "of immeasurable value or worth; invaluable."

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