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Definition of Tethyodea
1. n. pl. A division of Tunicata including the common attached ascidians, both simple and compound. Called also Tethioidea.
Medical Definition of Tethyodea
1. 
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1. n. pl. A division of Tunicata including the common attached ascidians, both simple and compound. Called also Tethioidea.
1.