Difference between Rear End and Backside

REAR END vs BACKSIDE: NOUN

The buttocks.
The side of something that is opposite the front.
The hinder part, posteriors, or rump of a person or animal.
The back premises, back yard, or out-buildings attached to a dwelling; also, the privy.
Specifically The hind part of an animal; the rump: often (vulgarly) in the plural.
The back part or aspect of anything; the part opposite to the front, or behind that which is presented to a spectator.
The buttocks; the rump.
The fleshy part of the human body that you sit on
The side of an object that is opposite its front

Rump, Tush, Buttocks, Ass, Keister, Bum, Derriere, Seat, Hindquarters, Butt, Posterior, Bottom, Backside, Tail, Rear

Arse, Prat, Rump, Tail, Rear, Posterior, Keister, Buttocks, Bum, Tush, Ass, Derriere, Hindquarters, Fanny, Butt

Rump, Tush, Buttocks, Ass, Keister, Bum, Derriere, Seat, Hindquarters, Butt, Posterior, Bottom, Backside, Tail, Rear

Arse, Prat, Rump, Tail, Rear, Posterior, Keister, Buttocks, Bum, Tush, Ass, Derriere, Hindquarters, Fanny, Butt

The only negative to the tray is the reduction in weight over the rear axle, which has resulted in a noticeably stiffer rear end.
The 105.2kg machine now has a single piece rear end while the rear brake now has an integrated reservoir.
The fuel tank is positioned in front of the rear axle to prevent it from being damaged or ruptured in a rear end impact.
And a new reflector trim bar between the LED rear lights gives the typical rear end of the car even more dynamic character.
The rear end of the Chevrolet crashed into the rear end of the squad car.
These rear end covers are designed to strengthen the rear housing case, specifically in heavy torque situations.
The rear end was squared off featuring large rear quarter windows to eliminate blind spots.
Posi rear end, traction bars, power windows, rear defroster, cruise, tilt wheel, all factory.
If the rear end keeps bouncing, your rear shocks may be worn.
The rear end and rear lights are especially unattractive.