恩が有る[ongaaru] to be in one's debt
恩を仇で返す[onwoadadekaesu] to return evil for good
恩愛[onai] kindness and affection
恩給[onkyuu] pension
恩恵[onkei] grace

恩顧[onko] favour
恩師[onshi] one's honoured teacher
恩賜[onshi] Imperial gift
恩赦[onsha] amnesty

恩讐[onshuu] love and hate
復讐[fukushuu] revenge
復讐の念[fukushuunonen] desire for vengeance
復讐劇[fukushuugeki] revenge tragedy

復讐心[fukushuushin] desire for revenge
復讐戦[fukushuusen] return match
君父の讐は倶に天を戴かず[kunpunoadahatomonitenwoitadakazu] not wanting to live in the same world as one's father's or lord's enemies
復讐者[fukushuusha] avenger