sea urchin

2 definitions found

sea urchin - Collaborative International Dictionary of English v.0.48 :

  Sea urchin \Sea" ur"chin\ (Zool.)
     Any one of numerous species of echinoderms of the order
     Echinoidea.
  
     Note: When living they are covered with movable spines which
           are often long and sharp.
           [1913 Webster]

sea urchin - WordNet (r) 2.1 (2005) :

  sea urchin
      n 1: shallow-water echinoderms having soft bodies enclosed in
           thin spiny globular shells