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Definition of Sao
1. n. Any marine annelid of the genus Hyalinæcia, especially H. tubicola of Europe, which inhabits a transparent movable tube resembling a quill in color and texture.
Medical Definition of Sao
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1. n. Any marine annelid of the genus Hyalinæcia, especially H. tubicola of Europe, which inhabits a transparent movable tube resembling a quill in color and texture.
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