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

cetacea \ceta"cea\, n. pl. nl., from l. cetus whale, gr. ?.
   zool.
   an order of marine mammals, including the whales. like
   ordinary mammals they breathe by means of lungs, and bring
   forth living young which they suckle for some time. the
   anterior limbs are changed to paddles; the tail flukes are
   horizontal. there are two living suborders:
   a {the mysticete or whalebone whales, having no true
       teeth after birth, but with a series of plates of
       whalebone see baleen. hanging down from the upper jaw
       on each side, thus making a strainer, through which they
       receive the small animals upon which they feed.}
   b {the denticete, including the dolphins and sperm whale,
       which have teeth. another suborder zeuglodontia is
       extinct. the sirenia were formerly included in the
       cetacea, but are now made a separate order.}
       1913 webster
see also:
mysticete baleen denticete zeuglodontia sirenia 

[2] : WordNet (r) 2.0

cetacea
     n : an order of eutheria syn: order cetacea
see also:
order cetacea 

Cetacea >> C Words
Cetacea, definition of term: Cetacea
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