八竿子打不着

1. • unrelated lacking any connection

     coll.

Character by character

• 八(bā)eight
• 竿(gān)pole
• 子(zi)noun suffix, as in 椅子 yǐzi "chair"
• 打(dǎ)a semantically light, transitive verb that is combined with various grammatical objects to form compound verbs and verb-object phrases with a diverse range of meanings
• 不(bù)no
• 着(zháo)touch