idioms involving “back”

Go behind someone’s back

Do something secretly without someone’s permission

“The boss refused to listen so the employee went behind his back to the boss’s boss.”

On the back of an envelope

A rough draft or very early version

“We’ve sketched out the campaign on the back of an envelope but need another week to prepare the presentation.”

Back-scratching

To help someone, knowing they will help you in return

“Sugita-san is doing a bit of back scratching by offering free photos to the magazine.”

A stab in the back

An undeserved action that hurts or betrays someone

“Mere-san, a loyal employee for 20 years, considered her boss’s poor evaluation of her work to be a stab in the back.”

Get off one’s back

To stop criticizing or bothering one

“Get off Sato-san’s back. He is working night and day to make this project succeed.”