A taxonomic <xref>genus</xref> within the <xref>family</xref> <xref>Ostreidae</xref> — <xref>marine</xref> <xref>bivalves</xref>, having a <xref>pearly</xref> interior, allied to the pearl <xref>oyster</xref>; so called from a supposed resemblance of the typical species to a bird.