南箕北斗

1. • lit. the Winnowing Basket in the southern sky, and the Big Dipper in the north (idiom)
2. • fig. sth which, despite its name, is of no practical use

Character by character

• 南(nán)surname Nan
• 箕(jī)winnow basket
• 北(běi)north
• 斗(dǒu)dry measure for grain equal to ten 升 shēng or one-tenth of a 石 dàn