Arachnida

 
Pronunciation: /əˈraknɪdə/

plural noun

Zoology
  • a class of chelicerate arthropods that includes spiders, scorpions, mites, and ticks. They have become adapted for a terrestrial life and possess both lungs and tracheae, and many have silk or poison glands.

Origin:

modern Latin (plural), from Greek arakhnē 'spider'