Used to refer to one's own second son or someone else's second son. Compare with 次男 (じなん), which is more common.
See also: 次男 (じなん)
He is the second son, with an older brother and a younger brother.
man between 17 and 20 years old (ritsuryō system)
Archaic term from the ritsuryō legal system. Not used in modern Japanese.
See also: 少丁
Under the ritsuryō system, 中男 referred to males between 17 and 20 years old.
Compound of 中 (ちゅう, 'middle') and 男 (なん, 'man' or 'son'). The archaic sense derives from the ritsuryō legal code, where it designated a specific age group for taxation and labor.