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adjective in·valu·able \(ˌ)in-ˈval-yə-bəl, -yə-wə-bəl, -yü(-ə)-bəl\

Simple Definition of invaluable

  • : extremely valuable or useful

Source: Merriam-Webster's Learner's Dictionary

Full Definition of invaluable

  1. :  valuable beyond estimation :  priceless <providing invaluable assistance>

invaluableness noun
invaluably play \-blē\ adverb

Examples of invaluable in a sentence

  1. Unfortunately, though, Sally does not respond to lithium, which has been invaluable for many patients with manic-depressive illness … —Oliver Sacks, New York Review of Books, 25 Sept. 2008

  2. I stayed there only a month or so but it was an invaluable experience … : that month's residence provided the inspiration for a novel I wrote much later, Sophie's Choice. —William Styron, This Quiet Dust and Other Writings, (1953) 1982

  3. … the scrolls provide an invaluable snapshot of at least one important strain in early Judaism—though they are by no means a complete record of Jewish belief at that time. —Jeremy Lott, Lingua Franca, February 2001

  4. Their help has been invaluable to us.

  5. <the list of likely donors proved to be invaluable to our fund-raising efforts>

invaluable = valuable?

Many people find it confusing that the in- prefix at the beginning of invaluable apparently lacks the meaning "not" found in a number of other words, such as invalid, inarticulate, and insane. In fact, the prefix does indicate negation, but in a way that is not immediately obvious. The original (and current) meaning of invaluable is "valuable beyond estimation"; the word describes something so precious that one cannot assign a price to it. This, clearly, is the opposite of the meaning "having no value; valueless" that the word might seem to carry. Invaluable actually has been recorded in the sense "without value," but such use has been exceedingly rare and is practically nonexistent today.

Origin of invaluable

1in- + value, verb + -able

First Known Use: 1576

INVALUABLE Defined for Kids


adjective in·valu·able \in-ˈval-yə-wə-bəl\

Definition of invaluable for Students

  1. :  priceless <… his advice and counsel will prove invaluable in dealing with such problems as might arise. — Robert Lawson, Rabbit Hill>

Seen and Heard

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tending to dismiss important matters

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