What is the definition of delayed puberty in boys?

Delayed puberty in boys is specifically defined as the absence of testicular enlargement by age 14. This benchmark is crucial because testicular enlargement is typically the first physical sign of puberty in boys, marking the onset of sexual maturation. By this age, most boys will have begun to experience some physical developments associated with puberty, such as testicular enlargement, and if this has not occurred, further evaluation may be warranted to assess for any underlying concerns.

The other options relate to signs of puberty, such as voice changes and the development of axillary hair, but these are not the primary indicators for diagnosing delayed puberty. Testicular enlargement remains the key milestone that signifies the start of puberty, which is why its absence by age 14 is the defining characteristic in determining delayed puberty in males.