What phase of micturition refers to the process of voiding urine?

The phase of micturition that refers to the process of voiding urine is the urination phase. During this phase, the bladder contracts, and the internal and external urethral sphincters relax, allowing urine to flow from the bladder through the urethra and out of the body. This process is typically initiated when the bladder reaches a certain level of fullness, signaling the brain to trigger the necessary actions for urination.

In contrast, the filling phase involves the bladder gradually filling with urine, and the storage phase encompasses the period when urine is retained in the bladder. The contraction phase could be interpreted in different contexts but does not specifically describe the act of voiding itself, as it may refer to the muscular contractions within various systems not limited to just urination. The urination phase is thus the most accurate descriptor of the actual process of expelling urine.