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

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Other Words from arachnid

arachnid adjective

Did You Know?

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 The footage shows a bat trapped in a spider’s web, with the arachnid waiting nearby. Fox News, "Woman catches spider eating a bat on the side of her house: 'I love the country'," 12 Aug. 2019 These arachnids can't fly or jump but rather wait for a host -- whether it be a mammal, bird, reptile or amphibian -- to feed on while resting on the tips of grasses and shrubs. Jen Christensen, CNN, "What is Lyme disease? Things you should know," 8 Jan. 2020 United Airlines confirmed that the arachnid stung one of its passenger on flight 1554 from San Francisco to Atlanta. Tara Law, Time, "A United Airlines Passenger Was Stung by a Scorpion While in the Air," 8 Dec. 2019 To gauge the arachnid species’ aggressive tendencies, Pruitt wrapped a mechanical toothbrush in wire and used it to poke a piece of paper intoA. studios spiders’ webs. Meilan Solly, Smithsonian, "Hurricanes Are Making This Spider Species More Aggressive," 20 Aug. 2019 As the name suggests, this species of arachnid is primarily found in states that border the Gulf of Mexico. Michael Reschke, Indianapolis Star, "Disease-causing tick common along Gulf Coast is now in Indiana, IU experts say," 23 Dec. 2019 Then, suddenly, an enormous arachnid-looking CGI creature with a face straight out of Scary Stories 3 bursts forth from the mire, struggling to fight off a warrior with luxurious Targaryen-Jimmy-Page hair who’s hacking away at its limbs. Judy Berman, Time, "Netflix’s The Witcher Is the Latest Disaster in a Year of Terrible Post-Game of Thrones Fantasy TV," 20 Dec. 2019 This time, no one was stung by the arachnid, but the flight was grounded, making for some prickly passengers, no doubt! Andrea Wurzburger,, "11 Horrifying Times Animals Made Their Way Onto Airplanes," 10 Dec. 2019 What message was this arachnid adornment supposed to convey to the nation, and indeed the world? Alexander Smith, NBC News, "Meet Lady Hale, the brooch-wearing justice who delivered a blow to Boris Johnson," 24 Sep. 2019

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.

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First Known Use of arachnid

1826, in the meaning defined above

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Time Traveler for arachnid

Time Traveler

The first known use of arachnid was in 1826

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Statistics for arachnid

Last Updated

18 Feb 2020

Cite this Entry

“Arachnid.” Dictionary, Merriam-Webster, Accessed 9 Apr. 2020.

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More Definitions for arachnid


How to pronounce arachnid (audio)

English Language Learners Definition of arachnid

technical : a kind of animal that has eight legs and a body formed of two parts

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Rhyming Dictionary: Words that rhyme with arachnid

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

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