tar·​di·​grade | \ ˈtär-də-ˌgrād How to pronounce tardigrade (audio) \

Definition of tardigrade

: any of a phylum (Tardigrada) of microscopic invertebrates with four pairs of stout legs that live usually in water or damp moss

called also water bear

Examples of tardigrade in a Sentence

Recent Examples on the Web The tardigrade found to have this trait is called the Paramacrobiotus BLR strain. Megan Marples, CNN, "When this creature faces deadly radiation, glowing is the only option," 19 Oct. 2020 Now, scientists have discovered a new species of tardigrade that can endure ultraviolet (UV) light so lethal, it is regularly used to get rid of hard-to-kill viruses and bacteria. Lakshmi Supriya, Science | AAAS, "New species of water bear uses fluorescent ‘shield’ to survive lethal UV radiation," 13 Oct. 2020 But here, too, the tardigrade seems oddly prepared for life in space. William Herkewitz, Popular Mechanics, "Everything We Know About Tardigrades, the Only Animal That Can Survive in Space," 21 Aug. 2020 In its desiccated state, the tardigrade is ridiculously, almost absurdly resilient. William Herkewitz, Popular Mechanics, "Everything We Know About Tardigrades, the Only Animal That Can Survive in Space," 21 Aug. 2020 Since tardigrades are mostly colorless, deCarvalho used fluorescent dye molecules to stain the tardigrade’s internal structures, revealing an eye-popping look inside a creature that typically grows no longer than one millimeter in length. Nora Mcgreevy, Smithsonian Magazine, "Colorful Image Lights Up Microscopic Guts of ‘Water Bear’," 13 Apr. 2020 Each sphere is teeming with invertebrate life, hosting creatures such as tardigrades, commonly known as water bears. Candice Wang, Popular Science, "Glacier mice have no feet, but they still move in herds," 28 May 2020 Tough tardigrades: Might in miniature Tardigrades—also known as water bears for their rotund bodies—are marvels of biology. National Geographic, "Insights on mighty ‘water bears,’ hardy seeds, and a new sensory organ," 9 Jan. 2020 More so than any other animal on Earth, the water bear (aka tardigrade, aka moss piglet) doesn’t particularly appreciate dying. Matt Simon, Wired, "Even Ultra-Tough Water Bears May Be Vulnerable to Climate Change," 16 Jan. 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'tardigrade.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of tardigrade

1860, in the meaning defined above

History and Etymology for tardigrade

ultimately from Latin tardigradus slow-moving, from tardus slow + gradi to step, go — more at grade entry 1

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Time Traveler for tardigrade

Time Traveler

The first known use of tardigrade was in 1860

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Statistics for tardigrade

Last Updated

7 Dec 2020

Cite this Entry

“Tardigrade.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/tardigrade. Accessed 22 Jan. 2021.

More from Merriam-Webster on tardigrade

Britannica.com: Encyclopedia article about tardigrade

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