backside
/ˈbækˌsaɪd/Definitions
1. noun
The part of the body on the opposite side of the front; the buttocks.
“She fell onto her backside and scraped her knee.”
2. noun
The reverse side of something, especially a surface or an object.
“The backside of the painting revealed a hidden message.”
3. noun
The rear part of a vehicle, especially a car or a motorcycle.
“The backside of the car was damaged in the accident.”
4. verb
To turn or face something to the rear.
“He backed his car out of the garage.”
5. verb
To move in the opposite direction; to retreat.
“The army backed off from the enemy’s position.”