Arachnida

noun plural

Arach·​ni·​da ə-ˈrak-nəd-ə How to pronounce Arachnida (audio)
: a large class of arthropods that are mostly air-breathing by means of trachea or book lungs, that include the spiders and scorpions, mites, and ticks, and that have a segmented body divided into two regions of which the anterior bears four pairs of legs but no antennae
arachnid adjective or noun

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Cite this Entry

“Arachnida.” Merriam-Webster.com Medical Dictionary, Merriam-Webster, https://www.merriam-webster.com/medical/Arachnida. Accessed 26 Jan. 2023.

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