Ureter
From Knoesis wiki
"The ureter is one of a pair of thick-walled tubes that transports urine from the kidney pelvis to the urinary bladder[GO]. Muscular duct that propels urine from the kidneys to the urinary bladder, or related organs. In humans, organ with organ cavity which connects the renal sinus to the urinary bladder. Examples: There are only two ureters, the right and the left ureters." [Wikipedia:Ureter]