abnormal efferent ductules of testis morphology dilated efferent ductules of testis MP:0009140 MPheno.ontology an expansion in the volume or area of the lumen of the small seminal ducts that lead from the testis to the head of the epididymis, usually with an increase in contained fluid dilated ductuli efferentes testis dilated efferent ducts dilated vas efferens efferent ductules of testis dilation