• WordNet 3.6
    • adj abactinal (of radiate animals) located on the surface or end opposite to that on which the mouth is situated
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Webster's Revised Unabridged Dictionary
    • a Abactinal (Zoöl) Pertaining to the surface or end opposite to the mouth in a radiate animal; -- opposed to actinal. "The aboral or abactinal area."
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Century Dictionary and Cyclopedia
    • abactinal In zoology, remote from the actinal or oral area; hence, devoid of rays; aboral. The abactinal surface may be either the upper or lower surface, according to the position of the mouth.
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Chambers's Twentieth Century Dictionary
    • adj Abactinal ab-ak′ti-nal (zool.) remote from the actinal area, without rays
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Webster's Revised Unabridged Dictionary
L. ab, + E. actinal,


In literature:

These two series also differ from each other in the relations of the abactinal nerve-system.
"Encyclopaedia Britannica, 11th Edition, Volume 8, Slice 10" by Various