arachnid

American  

[uh-rak-nid] / əˈræk nɪd /

noun

1. any wingless, carnivorous arthropod of the class Arachnida, including spiders, scorpions, mites, ticks, and daddy-longlegs, having a body divided into two parts, the cephalothorax and the abdomen, and having eight appendages and no antennae.

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adjective

1. belonging or pertaining to the arachnids.

arachnid British  

/ əˈræknɪd /

noun

1. any terrestrial chelicerate arthropod of the class Arachnida, characterized by simple eyes and four pairs of legs. The group includes the spiders, scorpions, ticks, mites, and harvestmen

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arachnid Scientific  

/ ə-răk′nĭd /

1. Any of various arthropods of the class Arachnida, such as spiders, scorpions, mites, and ticks. Arthropods are characterized by four pairs of segmented legs and a body that is divided into two regions, the cephalothorax and the abdomen.

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Other Word Forms

• arachnidan adjective

Etymology

Origin of arachnid

1865–70; < New Latin Arachnida < Greek aráchn ( ē ) spider, spider's web + New Latin -ida -ida

Example Sentences

A map of the routes with arrows arching across the country gave the operation its arachnid moniker.

From The Wall Street Journal • Dec. 10, 2025

The team that found the tiny orange-legged arachnid has informally named it the white-knuckled wolf spider.

From BBC • Oct. 30, 2025

Still, Waterhouse couldn’t shake her fascination with the sparklemuffin chic arachnid.

From Los Angeles Times • Sep. 13, 2024

This led the two scientists to conclude it doesn't belong in any of the known arachnid orders.

From Science Daily • May 17, 2024

Just because you’ve called something a spider once doesn’t mean that the next time you have to call it an arachnid or a predaceous eight-legged creepy-crawly.

From "Woe Is I" by Patricia T. O'Conner