Here is a list of idioms derived from the word arm.
Cost an arm and a leg
When something costs an arm and a leg, it is very pricey. This is an informal idiom.
- That laptop cost me an arm and a leg.
A shot in the arm
When you receive a shot in the arm, you get a sudden encouragement.
- This industry needs a shot in the arm in the form of foreign investment.
The long arm of the law
No one can escape the long arm of the law.
Twist somebody’s arm
When you twist somebody’s arm you persuade them to do something they don’t want to do.
- I didn’t want to go to the party, but Jane twisted my arm. (= Jane persuaded me to go.)
Keep somebody at arm’s length
When you keep somebody at arm’s length, you don’t allow them to be too friendly with you.
- I don’t know why she is keeping me at arm’s length.
- I always keep strangers at arm’s length.