• Webster's Revised Unabridged Dictionary
    • n. pl Prosobranchiata (Zoöl) The highest division, or subclass, of gastropod mollusks, including those that have the gills situated anteriorly, or forward of the heart, and the sexes separate.
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Century Dictionary and Cyclopedia
    • prosobranchiata An order or subclass of gastropods, having the gills anterior to the heart, generally breathing water, more or less completely inclosed in a univalve shell, and sexually distinct: opposed to Opisthobranchiata.
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Chambers's Twentieth Century Dictionary
    • Prosobranchiata pros-ō-brangk-i-ā′ta an order or sub-class of gasteropods having the gills anterior to the heart
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Webster's Revised Unabridged Dictionary
NL., fr. Gr. forward, further + a gill
Chambers's Twentieth Century Dictionary
Gr. prosō, forward, branchia, gills.


In literature:

Gasteropods of the first order have comb-like gills placed in advance of the heart, and are hence termed PROSOBRANCHIATA.
"Sea-Weeds, Shells and Fossils" by Peter Gray
They are connected with each other, rather like the pedal nerves of Chiton and the lower Prosobranchiata, by a number of commissures.
"The Works of Francis Maitland Balfour, Volume 1" by Francis Maitland Balfour