cryptorchidism

noun

1. (uncountable, usually)The failure of one or both testes to descend into the scrotum.

   “Other publications report a similar rate of 4–7%, but emphasize the influence of cryptorchidism, with which polyorchidism has been closely associated and which independently conveys an increased risk of testicular dysplasia [6], [9].”

   “In them, an examining doctor certified Hitler with a “right-side cryptorchidism” – not quite the missing ball of the British second world war song, but an undescended right testicle.”