testis
Meaning of testis: The formal name for the male gonad, used in anatomy and reports, where the plural testes and the adjective testicular both appear constantly.
Definition of testis
The testis is one of a pair of male reproductive glands lying in the scrotum, outside the main body cavity. Each holds coiled seminiferous tubules where sperm develop, and clusters of hormone producing cells that release testosterone into the bloodstream. Testis is the formal anatomical term and testicle the everyday equivalent; the plural of testis is testes.
Which word goes where?
| Form | Where it appears |
|---|---|
| Testis | Anatomical description, operative notes, pathology reports |
| Testes | The plural, as in undescended testes |
| Testicle and testicles | Everyday speech and most material written for patients |
| Testicular | The adjective, as in testicular cancer or testicular torsion |
| Orchi- and orchid- | Greek prefixes used in procedure names such as orchiectomy and orchiopexy |
All of these name the same organ. The mixture of Latin and Greek roots is the usual result of English medicine borrowing its nouns from Latin and its procedure names from Greek, so a report can describe the testis and then name the operation performed on it using an entirely different root.
What controls the testis?
Two pituitary hormones do the work, and each is aimed at a different cell population. Luteinizing hormone reaches the cells sitting between the tubules and prompts them to make testosterone. Follicle-stimulating hormone reaches the supporting cells inside the tubules and sustains sperm production. Above the pituitary, the hypothalamus sets the pace by releasing gonadotropin-releasing hormone in pulses. Testosterone circulating in the blood feeds back on both levels and slows the signal, closing a loop that holds output steady. This arrangement is why one hormone result rarely settles a question on its own: a low testosterone with high pituitary hormones points to the gland itself, while a low testosterone with low pituitary hormones points upward to the pituitary or the hypothalamus.
How does it connect to the rest of the tract?
Sperm leaving the tubules pass into a network of ducts at the back of the gland and then into the epididymis, a single coiled tube where they gain the ability to swim and are stored. From there the vas deferens carries them up through the inguinal canal into the abdomen, where fluid from the seminal vesicles and the prostate is added before ejaculation. The route is a legacy of where the organ started. Each testis forms high in the abdomen near the kidney and descends before birth, dragging its blood supply, nerves and duct behind it, which is why the artery to the testis begins near the kidney and why pain arising in the organ is often felt in the abdomen rather than the scrotum.
Also known as
Used in a sentence
Ultrasound of the scrotum was performed to further evaluate the palpable mass involving the right testis.
Good to know
Testis is the anatomical term used in clinical documentation, while testicle is the everyday equivalent, and both refer to the identical organ rather than two related but distinct structures.
Word origin
Where “testis” comes from
Formed from Latin testis, meaning witness.