Master the word " INVALUABLE " in English: definitions, translations, synonyms, pronunciations, examples, and grammar insights - all in one complete resource. What to Know Invaluable means “valuable beyond estimation,” making the word a near-synonym of valuable. This is because value as a verb can mean both “to prize or esteem” (“I value our friendship”) and also “to estimate or assign the monetary worth of” (“We value the painting at $1000”). It’s this second use that we find at the root of invaluable, meaning that its importance or worth is so great that it is impossible to calculate, close in meaning to priceless. The meaning of INVALUABLE is valuable beyond estimation : priceless. How to use invaluable in a sentence. invaluable = valuable? Although invaluable has a negative prefix, it is an adjective meaning extremely useful, indispensable or so valuable that a value can’t be set. Valuable implies a significant worth, usually in monetary terms.