What is the medical term for the act of voiding urine?

The medical term for the act of voiding urine is "micturition." This term specifically refers to the process by which urine is expelled from the bladder through the urethra. It encompasses the physiological and neurological mechanisms involved in urination, including the contraction of bladder muscles and the relaxation of sphincters.

Defecation, on the other hand, is the process of expelling solid waste from the digestive tract, which is distinctly different from micturition. Diuresis refers to increased production or excretion of urine, often as a result of medication or conditions affecting kidney function, rather than the act of voiding itself. Excretion is a broader term that encompasses the elimination of waste products from the body, including urine, but does not specifically denote the act of urinating.

Understanding these definitions clarifies why "micturition" is the correct choice for the act of voiding urine.