Macroorchidism
Abnormally large testes.
To determine if the testes are too large, a device called an orchidometer is used that permits the testes to be compared to a series of plastic ovals (like miniature American footballs) of differing sizes.
Macroorchidism is a diagnostic feature, for example, of the fragile X syndrome, the most common inherited form of mental retardation.
The opposite of macroorchidism is microorchidism (abnormally small testes).