To Backstab
To Betray
transitive verb, godan verb
If you cut someone from the backside you're doing a backstabbing, making this word to backstab or to betray.
The reading is 裏 plus 切る put together into one word.
彼女に裏切られて落ち込んでいるんです。
She betrayed me and I’m feeling depressed.
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.