invaluable

Invaluable is an adjective that means extremely useful or indispensable, and it is also used to mean priceless in terms of monetary or sentimental value. In modern usage, it often describes something of such importance that its value cannot be easily quantified.

Etymology and meaning nuance: The word comes from a combination of the prefix in- and valuare “to value,” originally implying “not able to be valued.” Over time, the sense shifted in common usage to emphasize extraordinary usefulness or priceless importance, rather than a straightforward negation of value. Many dictionaries now treat invaluable as meaning both “priceless” and “extremely useful,” with the latter sense being especially common in contemporary writing.

Usage and examples: Invaluable often describes advice, information, or resources that dramatically aid a effort. For example, "Her guidance was invaluable during the project" or "Access to the archival records proved invaluable for the researchers." Objects or experiences can also be described this way when their impact or usefulness is exceptional, as in "The donation provided invaluable support to the charity." A related term is priceless, which emphasizes irreplaceable worth beyond any price, while indispensable or irreplaceable convey necessity more than monetary value.

Common confusion and alternatives: Some readers interpret invaluable as a negation of value. In practice, it generally means extremely valuable or priceless, not simply “not valuable.” If the intention is to stress monetary price above all else, priceless is often a clearer choice; for emphasis on necessity, indispensable may be preferable.