arach·​nid | \ ə-ˈrak-nəd How to pronounce arachnid (audio) , -ˌnid \

Definition of arachnid

: any of a class (Arachnida) of arthropods comprising chiefly terrestrial invertebrates, including the spiders, scorpions, mites, and ticks, and having a segmented body divided into two regions of which the anterior bears four pairs of legs but no antennae

Other Words from arachnid

arachnid adjective

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The term arachnid refers to a class of animals that includes spiders, scorpions, mites, and ticks. Most arachnids have a segmented body divided into two regions, with the front part bearing four pairs of legs, but no antennae. They have a hard external skeleton and range in size from the mite, which is 0.003-in (0.08-mm) long, to the 8-in (21-cm) black scorpion of Africa. As arachnids grow, they molt, or shed their skin, several times. Arachnids are primarily carnivorous, but most are unable to digest food internally, instead they inject their prey with digestive fluids, then suck the liquefied remains. Arachnids are found worldwide in nearly every habitat. Some mites and ticks are parasitic and can carry diseases. Venomous spiders and scorpions also may pose a danger to humans, but most arachnids are harmless and prey only on insects.

Examples of arachnid in a Sentence

Spiders, scorpions, mites, and ticks are arachnids.
Recent Examples on the Web But as her fascination with Sting grows, so too does the arachnid’s size — and appetite for blood. Manori Ravindran, Variety, 6 May 2022 Researchers recently said the Joro spider, a large arachnid native to East Asia that proliferated in Georgia last year, could spread to much of the East Coast. CBS News, 12 Apr. 2022 The Joro spider, a colorful arachnid that can grow as big as the palm of your hand, has rapidly spread across the southeast and could be invading the east coast very soon. Claire Rafford, The Indianapolis Star, 10 Mar. 2022 The nocturnal arachnid lives within around 100km (62 miles) of Australia’s largest city, and is mostly active between November and April. NBC News, 3 Mar. 2022 Of course, many Scorpios like to get the venomous arachnid to represent their water sign. Gabi Thorne, Allure, 2 Feb. 2022 These arachnid architects have both astounded and puzzled scientists for ages, but a new study published last month in the journal Current Biology unravels the spiders' secrets. Rasha Aridi, Smithsonian Magazine, 24 Nov. 2021 Macbeth’s martial bonhomie seems unruffled by conflict, untroubled by the weird sisters’ prophecy, unmoved by Lady Macbeth’s arachnid schemes. Richard Brody, The New Yorker, 25 Dec. 2021 As befits a trickster, Anansi is a bit of a shape-shifter, alternately appearing as a large arachnid (his most frequent form), a human with the body of a spider or simply in the guise of an impish person. New York Times, 10 Nov. 2021 See More

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

First Known Use of arachnid

1826, in the meaning defined above

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The first known use of arachnid was in 1826

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Last Updated

11 May 2022

Cite this Entry

“Arachnid.” Dictionary, Merriam-Webster, Accessed 25 May. 2022.

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More from Merriam-Webster on arachnid

Nglish: Translation of arachnid for Spanish Speakers Encyclopedia article about arachnid


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