kidney - either of two bean-shaped excretory organs that filter wastes (especially urea) from the blood and excrete them and water in urine; urine passes out of the kidney through ureters to the bladder

apparatus urogenitalis, genitourinary apparatus, genitourinary system, systema urogenitale, urinary apparatus, urinary system, urogenital apparatus, urogenital system - the system that includes all organs involved in reproduction and in the formation and voidance of urine

tract - a system of body parts that together serve some particular purpose

urinary bladder - a membranous sac for temporary retention of urine

ureter - either of a pair of thick-walled tubes that carry urine from the kidney to the urinary bladder

urethra - duct through which urine is discharged in most mammals and which serves as the male genital duct