Pill bug

from WordNet (r) 3.0 (2006)
pill bug
    n 1: small terrestrial isopod with a convex segmented body that
         can roll up into a ball
    
from The Collaborative International Dictionary of English v.0.48
Pill \Pill\, n. [F. pilute, L. pilula a pill, little ball, dim.
   of L. pila a ball. Cf. {Piles}.]
   1. A medicine in the form of a little ball, or small round
      mass, to be swallowed whole.
      [1913 Webster]

   2. Figuratively, something offensive or nauseous which must
      be accepted or endured. --Udall.
      [1913 Webster]

   {Pill beetle} (Zool.), any small beetle of the genus
      {Byrrhus}, having a rounded body, with the head concealed
      beneath the thorax.

   {Pill bug} (Zool.), any terrestrial isopod of the genus
      {Armadillo}, having the habit of rolling itself into a
      ball when disturbed. Called also {pill wood louse}.
      [1913 Webster]
    

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