Medical Definition of sphincter urethrae
: a muscle composed of fibers that arise from the inferior ramus of the ischium and that interdigitate with those from the opposite side of the body to form in the male a narrow ring of muscle around the urethra just distal to the apex of the prostate gland and in the female a ring of muscle more generally distributed around the urethra—called also urethral sphincter
Seen and Heard
What made you want to look up sphincter urethrae? Please tell us where you read or heard it (including the quote, if possible).