(redirected from Ball sack)
Also found in: Dictionary, Thesaurus, Medical.


testis (tĕsˈtĭs) or testicle (tĕsˈtĭkəl), one of a pair of glands that produce the male reproductive cells, or sperm. In fetal life the testes develop in the abdomen, then descend into an external sac, the scrotum. A testis is composed of about 800 coiled seminiferous tubules whose linings contain cells that develop into sperm. These tubules merge into a larger tube called the epididymis that leads out of the testis into the vas deferens. Between the seminiferous tubules there is interstitial tissue that secretes the male sex hormone testosterone, which stimulates the development of the male reproductive system and secondary sex characteristics. Sometimes the testes do not descend normally before or shortly after birth and remain in the abdomen or groin. Such a condition requires medical attention or the gland will eventually become sterile. See also reproductive system.
The Columbia Electronic Encyclopedia™ Copyright © 2022, Columbia University Press. Licensed from Columbia University Press. All rights reserved.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



a musculocutaneous, sacciform structure in man and most viviparous mammals. In man a septum divides the scrotum into two halves, each of which contains a testis and epididymis, as well as the scrotal section of a spermatic cord. The scrotum is composed of several distinct layers: the skin, the dartos, several fasciae, and a muscular layer. The scrotum develops during the third month of pregnancy.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.


The pouch containing the testes.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.


the pouch of skin containing the testes in most mammals
Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005