ultrapure

• ultra-pure

ultra- +‎ pure

• (Received Pronunciation) IPA^(key): /ˈʌltɹəˈpjʊə/, /ˈʌltɹəˈpjɔː/
• (US) IPA^(key): /ˈʌltɹəˈpjʊɹ/, /ˈʌltɹəˈpjɔɹ/

ultrapure (comparative more ultrapure, superlative most ultrapure)

1. Extremely pure; of supreme purity.

   ultrapure water

   • 1923, The American Journal of Clinical Medicine‎, Winnetka, Ill., page 317:

     To quote Doctor Taylor further: "Certainly the laboratory and the factory which have cheapened food by canning and preserving it and the well-meaning legislator who has purified it, in some cases, perhaps, to the exclusion of the vitamines, owe to the public the corrective for machine-made, ultrapure and deceptive products."

   • 1926, Felix d' Herelle, The Bacteriophage and Its Behavior‎, Williams & Wilkins, page 207:

     We will see on the other hand that when the symbiotic association has continued for a long time it may be very difficult to obtain ultrapure colonies. In this last case it is necessary to adopt special methods of isolation.

   • 1977, United States Congress, Congressional Record‎, Washington, The Congress, page 34264:

     The very high cost of ultrapure semiconductor silicon has been a barrier to lowering the cost of solar cells. Metallurgical-grade silicon has a purity as high as 99 percent, and it costs 10 to 20 cents per pound, roughly the same cost as steel. The semiconductor-grade silicon, used In solar cells, however, has a purity of 99.99999 percent and costs $10 to $20 a pound.

ultrapure

1. feminine plural of ultrapuro