To strike back or retaliate (even if only slightly) against an opponent's attack or criticism; an idiomatic expression often used figuratively.
彼の激しい批判に対し、私も一矢を報いるつもりで反論した。
In response to his harsh criticism, I replied to strike back, even if only a little.
試合では最後に一矢を報いるチャンスが来たが、決められなかった。
In the match there was a final chance to strike back, but it couldn't be converted.
歴史家は小さな出来事を取り上げて、その時代の人々が一矢を報いる場面を描いている。
The historian highlights small incidents that show people of the era striking back in some way.