Definition of "testis" [tes•tis]

• The reproductive gland in a male vertebrate, the source of spermatozoa and the androgens, normally occurring paired in an external scrotum in humans and certain other mammals. (noun)
• An analogous gland in an invertebrate animal, such as a hydra or a mollusk. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "The receptors are everywhere, but the testis is exquisitely sensitive to the drug."
• "From my own observations, I am led to believe that no such muscular structure as a gubernaculum exists, and therefore that the descent of the testis is the effect of another cause."
• "The one above the testis is the plica vascularis, and contains ultimately the internal spermatic vessels; the one below, the plica gubernatrix, contains the lower part of the gubernaculum, which has now grown into a thick cord; it ends below at the abdominal inguinal ring in a tube of peritoneum, the saccus vaginalis, which protrudes itself down the inguinal canal."