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ultrathin

American  
[uhl-truh-thin] / ˌʌl trəˈθɪn /

adjective

  1. extremely thin.

    an ultrathin wristwatch.


Etymology

Origin of ultrathin

First recorded in 1945–50; ultra- + thin

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

To keep making electronics smaller and more powerful, researchers are investigating ways to combine silicon with new ultrathin materials.

From Science Daily • Jun. 17, 2026

These include ultrathin broadband polarizers that control the direction of light in compact optical systems, as well as sub-diffractional waveguides capable of guiding light through spaces smaller than those allowed by conventional optics.

From Science Daily • Jun. 1, 2026

These emitters are made from stacked ultrathin metal layers.

From Science Daily • Mar. 17, 2026

It was a pioneer in developing glass fiber, in which threads of ultrathin glass are woven together like a fabric.

From The Wall Street Journal • Feb. 8, 2026

An ultrathin gold rope trailed from the fletching.

From "The Son of Neptune" by Rick Riordan

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