Arachnida
noun plural
Arach·ni·da
ə-ˈrak-nəd-ə 
: 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
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“Arachnida.” Merriam-Webster.com Medical Dictionary, Merriam-Webster, https://www.merriam-webster.com/medical/Arachnida. Accessed 4 Mar. 2025.
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