Final answer:
The word that means dilation or expansion of the ureters is hydroureter.
Step-by-step explanation:
The word that means dilation or expansion of the ureters is hydroureter. Hydroureter occurs when the ureters become enlarged or dilated due to a blockage or obstruction that prevents the normal flow of urine from the kidneys to the bladder. This can be caused by conditions such as kidney stones, urinary tract infections, or tumors.