破瓜

The shape of the character 瓜 can be decomposed into two 八 (“eight”), thus “breaking 瓜” is used to euphemistically refer to reaching the age of 8+8 (=16) for girls, and 8×8 (=64) for men.

破瓜

1. (literary, of a girl) to reach the age of 16
2. (literary, figurative, of a girl) to lose one's virginity
3. (literary, of a man) to reach the age of 64

• 開瓜／开瓜 (“to take a woman's virginity”)
• 破身 (“to have sexual intercourse for the first time”)

Japanese Wikipedia has an article on:

破瓜

Wikipedia ^ja

Similar to the sense development of Chinese 破瓜 (pòguā), the shape of the character 瓜 (literally “gourd”) can be 破 (“broken”) or decomposed into two 八 (“eight”) characters, thus “breaking 瓜” is used to euphemistically refer to reaching the age of 8+8 (=16) for girls, and 8×8 (=64) for men.^[1][2][3][4]

The girls' age sense is cited to the late 1600s. The men's age sense is cited to the early 1700s. The sexual sense is cited to the late 1800s.^[1]

• (Tokyo) はか (Atamadaka – )^[3][4]
• IPA^(key):

破(は)瓜(か) • (haka) ^{←はくわ (fakwa)?}

1. the age of 16 for a girl
2. the age of 64 for a man
3. (by extension from the age 16 sense) the breaking of the hymen through sexual intercourse
4. (by extension from the age 16 sense) hebephrenia, disorganized schizophrenia: a type of schizophrenia with onset typically occurring during adolescence

   Synonyms: 破瓜病 (hakabyō), 破瓜型総合失調症 (haka-kei sōgō shitchō-shō)

• 破(は)瓜(か)期(き) (hakaki): adolescence, puberty
• 破(は)瓜(か)病(びょう) (hakabyō): hebephrenia