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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.

In a new study published in Nature Materials, physicists led by researchers at The University of Texas at Austin observed a sequence of unusual magnetic states in an ultrathin material.

From Science Daily • Mar. 7, 2026

So he made an Apple store appointment to buy the new, ultrathin smartphone the day it went on sale.

From The Wall Street Journal • Nov. 8, 2025

Elsewhere in the plant, workers cut the ingots into ultrathin wafers using diamond wire saws.

From Barron's • Nov. 7, 2025

Apple had intended the ad to send the opposite message, that its ultrathin iPad Pro could power an array of creative activities that previously required individual tools.

From New York Times • May 9, 2024

An ultrathin gold rope trailed from the fletching.

From "The Son of Neptune" by Rick Riordan