porcupine

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun Any of various rodents of the family Hystricidae, of Eurasia and Africa, or the family Erethizontidae, of the Americas, having long, sharp, erectile quills.

from The Century Dictionary.

• To cause to stand up like a porcupine's quills.
• noun A hystricomorphic rodent quadruped of the family Hystricidæ, of which there are several genera and many species, representing two subfamilies, the Hystricinæ or Old World porcupines, which are all terrestrial and fossorial animals, and the Sphingurinæ or New World porcupines, more or less arboreal, and in some cases having a prehensile tail.
• noun An apparatus for heckling flax.
• noun A cylindrical heckle for worsted yarn.

from the GNU version of the Collaborative International Dictionary of English.

• noun (Zoöl.) Any Old Word rodent of the genus Hystrix, having the back covered with long, sharp, erectile spines or quills, sometimes a foot long. The common species of Europe and Asia (Hystrix cristata) is the best known.
• noun (Zoöl.) Any species of Erethizon and related genera, native of America. They are related to the true porcupines, but have shorter spines, and are arboreal in their habits. The Canada porcupine (Erethizon dorsatus) is a well known species.
• noun (Zoöl.) the echidna.
• noun (Zoöl.) a large spiny Japanese crab (Acantholithodes hystrix).
• noun (Med.) See Ichthyosis.
• noun (Zoöl.) any plectognath fish having the body covered with spines which become erect when the body is inflated. See Diodon, and Globefish.
• noun (Bot.) a grass (Stipa spartea) with grains bearing a stout twisted awn, which, by coiling and uncoiling through changes in moisture, propels the sharp-pointed and barbellate grain into the wool and flesh of sheep. It is found from Illinois westward. See Illustration in Appendix.
• noun (Bot.) the hard outer wood of the cocoa palm; -- so called because, when cut horizontally, the markings of the wood resemble the quills of a porcupine.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun Any of several rodents covered with stiff, sharp, erectile, spines or quills (that stand straight up when the animal is attacked or surprised), belonging to one of two taxonomic families: Hystricidae (Old World porcupines) and Erethizontidae (New World porcupines).

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun relatively large rodents with sharp erectile bristles mingled with the fur