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 (ăk′tĭ-nəl, ăk-tī′-)
Of, relating to, or located on the part of a radially symmetric animal from which the tentacles radiate or the side where the oral area is found.

ac′ti·nal·ly adv.


(ˈæktɪnəl; ækˈtaɪnəl)
1. (Zoology) of or denoting the oral part of a radiate animal, such as a jellyfish, sea anemone, or sponge, from which the rays, tentacles, or arms grow
2. (Zoology) possessing rays or tentacles, as a jellyfish
[C19: see actino-, -al1]
ˈactinally adv
ThesaurusAntonymsRelated WordsSynonymsLegend:
Adj.1.actinal - (of radiate organisms) located on the surface or end on which the mouth is situatedactinal - (of radiate organisms) located on the surface or end on which the mouth is situated
organism, being - a living thing that has (or can develop) the ability to act or function independently
abactinal - (of radiate animals) located on the surface or end opposite to that on which the mouth is situated
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References in periodicals archive ?
Morphological features of the samples were observed by naked eye (aboral and oral view) followed by inspection on abactinal (aboral) and actinal (oral) surfaces and terminals (arm tips), whereas detailed observations were done with aid of Olympus SZ 51 stereomicroscope.
Approximately 15 days after fertilization, settlers have more pronounced pentamerous symmetry, the abactinal and actinal regions become distinct, the dorsal spines become more developed (most numerous in the margins), and the eyespot is fully formed (Fig.
Superficie actinal con placas actinales teseladas, cada una con una protuberancia rodeada por pequenos granulos.