The fibromuscular tubular canal through which urine is discharged from the bladder to the exterior via the external urinary meatus; in males, the urethra is joined by the ejaculatory ducts and serves as a passageway for semen during ejaculation, as well as a canal for urine during voiding; in females, the urethra is shorter and emerges above the vaginal opening. [ http://www.informatics.jax.org/accession/anna MP:0000537 ]