• Webster's Revised Unabridged Dictionary
    • n Bipinnaria (Zoöl) The larva of certain starfishes as developed in the free-swimming stage.
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Century Dictionary and Cyclopedia
    • n bipinnaria A generic name given to the bilateral larval form of some echinoderms, as a starfish, under the impression that it was a distinct animal: nearly the same as Brachiolaria. The term is retained to designate such larvæ or stage of development. See also cut under Asteroidea.
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Webster's Revised Unabridged Dictionary
NL., fr. L. bis, twice + pinna, feather


In literature:

Larva of Starfish (Bipinnaria), x 100.
"On the Origin and Metamorphoses of Insects" by Sir John Lubbock
Thus the larvae of the starfishes were called Bipinnaria, the larvae of the sea-urchins Pluteus, and so on.
"Elementary Zoology, Second Edition" by Vernon L. Kellogg