ultrahigh

adjective
ul·​tra·​high | \ ˌəl-trə-ˈhī How to pronounce ultrahigh (audio) \

Definition of ultrahigh

: extremely or extraordinarily high ultrahigh speeds/temperatures a car designed for ultrahigh performance Eager to catch shoppers' eyes, television manufacturers are shipping TVs from the factory with brightness and contrast set ultrahigh.— Evan Ramstad

First Known Use of ultrahigh

1822, in the meaning defined above

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