[ uhl-truh-thin ]

  1. extremely thin: an ultrathin wristwatch.

Origin of ultrathin

First recorded in 1945–50; ultra- + thin

Words Nearby ultrathin

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use ultrathin in a sentence

  • The researchers envision the new design being made into ultrathin films or coatings and wrapped around implants to passively power electronics, using the body’s abundant glucose supply.

    Sugar rush | Jennifer Chu | August 24, 2022 | MIT Technology Review
  • The researchers’ deceptively simple fabrication technique requires only three basic steps and can be scaled up to produce ultrathin loudspeakers large enough to cover the inside of an automobile or to wallpaper a room.

  • Made from an ultrathin and stretchy polyester-spandex blend, it vented and wicked sweat even better than the Stio Eddy, so it was the first top I reached for when the forecast called for temperatures above 100 degrees.

  • The stretchy polyester fabric is ultrathin and comfortable but cuts the chill just enough on cold mornings.