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

Dictionary Entries Near Arachnida

Cite this Entry

“Arachnida.” Medical Dictionary, Merriam-Webster, Accessed 19 Jul. 2024.

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