invaluable

English

in- +‎ valuable (compare priceless).

invaluable (comparative more invaluable, superlative most invaluable)

Having great or incalculable value.
Synonyms: valuable, precious, crucial
- 1813, Jane Austen, Pride and Prejudice:
  You are a very strange creature by way of a friend!—always wanting me to play and sing before anybody and everybody! If my vanity had taken a musical turn, you would have been invaluable; but as it is, I would really rather not sit down before those who must be in the habit of hearing the very best performers.
- 1961, Joseph Heller, Catch-22, page 181:
  Colonel Cathcart bewailed the miserable fate that had given him for an invaluable assistant someone as common as Colonel Korn. It was degrading to have to to depend so thoroughly on a person who had been educated at a state university.
(obsolete) Not valuable; worthless.
- 1640, Treaty of Ripon:
  The money I have received is so invaluable a sum that I have forborne as yet to pay it in, and am heartily sorry that I cannot better advance His Majesty's service.
- 1866, Thomas Wright, The Intellectual Observer:
  It would be an interesting, and far from an invaluable labour, to trace the history of the murrains, or cattle diseases of former days, and there causes and effects.

of great value

Armenian: անգին (hy) (angin)
Bulgarian: безценен (bg) (bezcenen)
Chinese:
Mandarin: 無法估價的／无法估价的 (wúfǎ gūjià de)
Czech: nedocenitelný
Finnish: korvaamaton (fi)
French: inestimable (fr)
Greek: ανεκτίμητος (el) (anektímitos), πολύτιμος (el) (polýtimos)
Italian: prezioso (it), senza prezzo, impareggiabile (it), enorme (it), immenso (it)
Japanese: かけがえのない (kakegae no nai)
Kazakh: бағасыз (bağasyz)
Malayalam: വിലമതിക്കാനാവാത്ത (vilamatikkānāvātta), അമൂല്യ (ml) (amūlya)
Norwegian: uvurderlig
Occitan: inestimable, invalorable
Polish: nieoceniony, bezcenny (pl)
Portuguese: inestimável (pt)
Russian: бесце́нный (ru) (bescénnyj), неоценимый (ru) (neocenimyj)
Spanish: invalorable

very useful

of inestimable worth

Armenian: անգնահատելի (hy) (angnahateli)
Bulgarian: неоценим (bg) (neocenim)
Chinese:
Mandarin: 無價的／无价的 (wújià de)
Finnish: korvaamaton (fi), korvaamattoman arvokas
Italian: inestimabile (it), impagabile (it), incalcolabile (it)
Malayalam: വിലമതിക്കാനാവാത്ത (vilamatikkānāvātta), അമൂല്യ (ml) (amūlya), അമൂല്യമായ (amūlyamāya)
Polish: bezcenny (pl)
Russian: please add this translation if you can

invaluable (plural invaluables)