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Related to nephrostoma: Nephrostomy
one of the ciliated funnel-shaped orifices of the excretory tubules that open into the coelom in the embryo; best seen in lower vertebrates.
ne·phros·to·ma, nephrostome (ne-fros'tō-mă, nef'rō-stōm),
One of the ciliated funnel-shaped openings by which pronephric and some primordial mesonephric tubules communicate with the celom.
[nephro- + G. stoma, mouth]