(testis), a double part in animals of the male kind serving for the office of generation.—See Anatomy, n° 107. They are called testiculae, by diminution of testes, "witnesses;" as giving testimony of virility. The Greeks call them didymoi, or "twins."

In man and most animals, the testicles are exterior; in fowls, as fowls, interior. Some men have only one, ordinarily they have two; some have naturally had three; nay, anatomists assure us they have known four.