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Medical Term:


Pronunciation: spi'der


  1. An arthropod of the order Araneida (subclass Arachnida) characterized by four pairs of legs; a cephalothorax; a globose, smooth abdomen; and a complex of web-spinning spinnerets. Among the venomous spiders found in the New World are the black widow spider, Latrodectus mactans; red-legged widow spider, Latrodectus bishopi; pruning spider, or Peruvian tarantula, Glyptocranium gasteracanthoides; Chilean brown spider, Loxosceles laeta; Peruvian brown spider, Loxosceles rufipes; brown recluse spider of North America, Loxosceles reclusus.
  2. An obstructive growth in the teat of a cow.

[O. E. spinnan, to spin]

© Copyright 2016 Wolters Kluwer. All Rights Reserved. Review Date: Sep 19, 2016.