The urethra is the small tube that carries urine out of the body from the bladder, which is the bag where urine is stored. In men it is much longer, runs down through the penis, and does a second job as well: semen also leaves the body through it. In women it is short — only a few centimetres — and has just the one job. That length difference is why doctors say women get bladder infections far more often than men: bacteria have a much shorter journey in. It is a medical word, the ordinary and only word doctors use, and it is completely neutral to say — not rude, not embarrassing. But it is not a word that comes up in casual conversation; you will meet it at a clinic, in a health article, or in a biology class. Countable: one urethra, two urethras (or, in medical writing, urethrae). The adjective is 'urethral', as in 'a urethral infection'. Say it with the stress in the middle: yoo-REE-thra.