tar·​di·​grade | \ ˈtär-də-ˌgrād \

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 toughest Earth creature could be the water bear, or tardigrades, which are .04 inch long invertebrate animals that live in mosses, soil, or lichens on earth. Joe Pappalardo, Popular Mechanics, "What Would Life on Mars Be Like?," 25 July 2018 Scientists have been testing tardigrades for years, heating them up to 300 degrees and freezing them to –328 degrees Fahrenheit. National Geographic, "New Species of 'Indestructible' Animal Found in Surprising Place," 1 Mar. 2018 Some life forms—like tardigrades and certain species of bacteria and fungus—can survive for extended periods in the vacuum of space. Avery Thompson, Popular Mechanics, "Could Life on Earth Have Come From Space?," 18 May 2018 Like other tardigrades, M. shonaicus has a chunky body, eight legs and a round mouth. Brigit Katz, Smithsonian, "New Tardigrade Species Found in Parking Lot in Japan," 2 Mar. 2018 There’s talk of tardigrade fields and time vortexes, and Laurence Fishburne delivers a technically sound lecture on something called quantum decoherence. New York Times, "The Science (and the Scientists) Behind ‘Ant-Man’," 6 July 2018 With their superstrength coded into their DNA, tardigrades are already known for their toughness. David Grossman, Popular Mechanics, "New Tardigrade Species Found in Parking Lot," 28 Feb. 2018 Earth is home to remarkably sturdy life like the tardigrade. David Grossman, Popular Mechanics, "There Is Life That Can Reproduce in the Most Mars-Like Place on Earth," 27 Feb. 2018 Higgins was enamored by the tenacity of tardigrades, with their death-defying adaptions to desiccation, freezing, radiation, and other extreme environmental stresses. Adrienne Mason, Smithsonian, "King of The Mud Dragons," 2 Mar. 2018

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

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Last Updated

10 Dec 2018

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Time Traveler for tardigrade

The first known use of tardigrade was in 1860

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More from Merriam-Webster on tardigrade

Britannica.com: Encyclopedia article about tardigrade

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