Betrayal
Treachery
noun
From the backside you cut someone. Wow. What a jerk. What betrayal and treachery.
This word is 裏 and 切る's readings, put together.
それは裏切り行いですよ。
That is an act of betrayal.
友達と、マラソン大会で一しょにゴールしようねって言ってたのに、裏切られた。
My friends and I said we would finish the marathon together, but they betrayed me.
奴らは裏切り者を殺すのにこの施設を利用している。
They use this facility to kill traitors.