What is the etymology of 赤の他人?


> 彼は赤の他人だよ — He's a total stranger to me

How did "red stranger" come to mean "total stranger" in Japanese? Is there
anything that makes this expression make sense more than "That's just what it
means"?




The color term `赤` 'red' is historically related to `明るい` 'bright, clear' or
`明らか` 'evident'. From this, the `赤` in the expressions such as `赤の他人`,
`真っ赤な嘘`, or `赤っ恥` means 'clear, complete'. This will make them mean 'complete
stranger', 'complete lie', 'complete shameness'.




The color term `赤` 'red' is historically related to `明るい` 'bright, clear' or
`明らか` 'evident'. From this, the `赤` in the expressions such as `赤の他人`,
`真っ赤な嘘`, or `赤っ恥` means 'clear, complete'. This will make them mean 'complete
stranger', 'complete lie', 'complete shameness'.

