noun, noun, used as a suffix, counter
Used mainly in compounds or as a suffix/counter for sons. Not a standalone word for 'son' in modern Japanese; the common standalone word is 息子 (むすこ).
He is the third son.
The eldest son became a doctor.
The kanji 男 means 'man' or 'male'. The reading なん is the on'yomi, used in Sino-Japanese compounds. The specific meaning 'son' arises in compounds and counters.
fifth son
second son · man between 17 and 20 years old (ritsuryō system)
pious man; devout man
youngest son
female-to-male gender swap (in fan works)
transformation into a man; woman reborn as a man
eating sushi/sashimi off a naked man's body