testis

noun

tes·​tis ˈte-stəs 

plural testes ˈte-ˌstēz 

: a typically paired male reproductive gland that produces sperm and secretes testosterone and that in most mammals is contained within the scrotum at sexual maturity

Examples of testis in a Sentence

Recent Examples on the Web

In papers last year, the researchers showed that microplastics were present in human testes and placentas. —Nina Agrawal, New York Times, 8 Apr. 2025

As in other birds, each individual typically has either two testes that produce sperm or a single ovary that produces eggs. —Donna L. Maney, Scientific American, 18 Feb. 2025

These particles have been found in various bodily organs—including the kidney, liver, placenta and testes—although not at such concentrations as now seen in the brain, the team said. —Anders Fogh Rasmussen, Newsweek, 5 Feb. 2025

They have also been detected in human livers, kidneys, placentas, and testes. —Paul Smaglik, Discover Magazine, 4 Feb. 2025

Word History

Etymology

Latin, witness, testis

First Known Use

1650, in the meaning defined above

Rhymes for testis

• asbestos
• hephaestus

Kids Definition

testis

noun

tes·​tis ˈtes-təs 

plural testes ˈtes-ˌtēz 

: an oval-shaped male reproductive gland that produces sperm and secretes testosterone and that in most mammals is contained within the scrotum

Medical Definition

testis

noun

tes·​tis ˈtes-təs 

plural testes ˈtes-ˌtēz 

: a typically paired male reproductive gland that usually consists largely of seminiferous tubules from the epithelium of which spermatozoa develop, that contains androgen-secreting Leydig cells in the interstitial tissue, that corresponds to the ovary of the female and in craniate vertebrates develops from the genital ridges of the embryo, and that in most mammals descends into the scrotum before the attainment of sexual maturity and in many cases before birth