[1] : The Collaborative International Dictionary of English v.0.48

amphioxus \am`phiox"us\, n. nl., fr. gr. 'amfi` + ? sharp.
   zool.
   a fishlike creature amphioxus lanceolatus, two or three
   inches long, found in temperature seas; -- also called the
   lancelet. its body is pointed at both ends. it is the
   lowest and most generalized of the vertebrates, having
   neither brain, skull, vertebrae, nor red blood. it forms
   the type of the group acrania, leptocardia, etc.
   1913 webster
see also:
amphioxus lanceolatus lancelet acrania leptocardia 

[2] : WordNet (r) 2.0

amphioxus
     n : small translucent lancet-shaped burrowing marine animal;
         primitive forerunner of the vertebrates syn: lancelet
     also: amphioxi pl
see also:
lancelet amphioxi 

Amphioxus >> A Words
Amphioxus, definition of term: Amphioxus
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