ultrafine
adjective
ul·tra·fine
ˌəl-trə-ˈfīn 
: fine to an extreme degree: such as
a
: extremely small, thin, or precise
ultrafine dust particles
an ultrafine needle
Color "curves," meanwhile, allow ultrafine adjustments and targeting of color and brightness ranges …—
Alexander Breindel
Alexander Breindel
b
: of extremely high quality
ultrafine wines
Examples of ultrafine in a Sentence
Recent Examples on the Web
The smallest, what are called ultrafine particles, even slip through the alveolar capillary barrier itself, crossing into the bloodstream, and from there travel throughout the body, including to the heart, the brain, and the kidneys to initiate even more destruction and disease (see below).
—Bill Frist, Forbes.com, 18 Sep. 2025
The patch incorporates both microchannels for collecting sweat and an ultrafine nanoplasmonic structure—an optical sensor structure—that analyzes sweat components using light.
—Hannah Millington, MSNBC Newsweek, 17 Sep. 2025
Purdue University researchers have uncovered just what happens when hair-styling products meet heat, providing the first quantitative evidence that everyday haircare routines can be a significant source of indoor nanoparticle (or, more specifically, ultrafine particle) emissions.
—New Atlas, 23 Aug. 2025
Uneven coffee grinds, with lots of ultrafine particles or giant boulders, will cause uneven extraction.
—Matthew Korfhage, Wired News, 13 Aug. 2025
See All Example Sentences for ultrafine
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Bill Frist, Forbes.com, 18 Sep. 2025
The patch incorporates both microchannels for collecting sweat and an ultrafine nanoplasmonic structure—an optical sensor structure—that analyzes sweat components using light.
—Hannah Millington, MSNBC Newsweek, 17 Sep. 2025
Purdue University researchers have uncovered just what happens when hair-styling products meet heat, providing the first quantitative evidence that everyday haircare routines can be a significant source of indoor nanoparticle (or, more specifically, ultrafine particle) emissions.
—New Atlas, 23 Aug. 2025
Uneven coffee grinds, with lots of ultrafine particles or giant boulders, will cause uneven extraction.
—Matthew Korfhage, Wired News, 13 Aug. 2025
See All Example Sentences for ultrafine
Cite this Entry
“Ultrafine.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ultrafine. Accessed 31 Oct. 2025.
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