expression, noun
complete stranger; total stranger
Emphasizes that the person is utterly unrelated and unknown, with no connection whatsoever. Often used in contrast to family, friends, or acquaintances.
彼は私にとっては赤の他人だ。
He is a complete stranger to me.
赤の他人にそんなことを頼めない。
I can't ask a total stranger to do something like that.