ul·​tra·​cool ˌəl-trə-ˈkül How to pronounce ultracool (audio)
: extremely or extraordinarily cool
ultracool temperatures
At times, Miguel seemed calm, ultracool, and controlled …Kelly Fitzpatrick
especially, informal : very good or fashionable
bought an ultracool car

Word History

First Known Use

1868, in the meaning defined above

Time Traveler
The first known use of ultracool was in 1868

Dictionary Entries Near ultracool

Cite this Entry

“Ultracool.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ultracool. Accessed 28 Nov. 2023.

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