ul·​tra·​slow ˌəl-trə-ˈslō How to pronounce ultraslow (audio)
: moving with, exhibiting, or marked by extremely low speed : extremely or extraordinarily slow
ultraslow motion

Word History

First Known Use

1870, in the meaning defined above

Time Traveler
The first known use of ultraslow was in 1870

Dictionary Entries Near ultraslow

Cite this Entry

“Ultraslow.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ultraslow. Accessed 21 May. 2024.

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