backside

noun

back·​side ˈbak-ˌsīd 

1

informal

a

: the part of the body that a person sits on : buttocks

I slid down on my backside, heaving or rowing myself with my arms and using my good leg for steering …

—Oliver Sacks

b

: the part of the body of a four-legged animal corresponding to the buttocks : rump sense 1a

… admits she hit the dog's backside but denies hitting it on the head.

—Ann Krueger

2

or back side : the side or surface opposite the front or face of something : the farthest or reverse side : back

A tight, rocky couloir drops down the backside of the peak …

—Mike Beaudry

The guy with the clipboard pulled me over, pointed to an innocuous little knob on the back side of the engine and said it's part of the computer and needs to be replaced.

—Tom and Ray Magliozzi

3

or back side

a

: the side opposite the homestretch on a racecourse : backstretch

When challenged on the backside the final time around, Tudor Palm would have no part of it, and burst to the lead again.

—Jackie Burke

b

: the part of a playing field or court (as in football or basketball) that is away from where the main action or play is occurring

—often used before another noun

a backside tackle

c

: the final 9 holes of an 18-hole golf course

The duo had a little trouble on the backside, though, as they bogeyed the par-3 11th hole.

—Brian Girasoli

Synonyms of backside

• cheeks
• bum
• seat
• tail
• rump
• bottom
• rear

Examples of backside in a Sentence

our backsides were sore after sitting on those hard benches for so long

Recent Examples on the Web

Strong low pressure is pulling in northerly winds on its backside while spreading clouds and rain ahead of it, limiting daytime warming and helping the cooler air linger in place. —Brandi D. Addison, USA Today, 30 Apr. 2026

With the school board’s approval, the district will advance its plans to build a new elementary school on the backside of the site of Lake Hazel Elementary School. —Becca Savransky, Idaho Statesman, 29 Apr. 2026

The room full of journalists was very much enamored of the Orient Blue Alcantara backside on the Razr Ultra. —Florence Ion, PC Magazine, 29 Apr. 2026

The pair collided with such force that Dumoulin got knocked up about two feet in the air before landing hard on his padded backside. —Sean Keeler, Denver Post, 27 Apr. 2026

Word History

First Known Use

14th century, in the meaning defined at sense 2

Rhymes for backside

• abide
• allied
• applied
• aside
• astride
• azide
• bankside
• bastide
• bayside
• bedside
• belied
• beside

Kids Definition

backside

noun

back·​side ˈbak-ˈsīd 

informal

: buttock sense 2a

Medical Definition

backside

noun

back·​side -ˌsīd 

: buttocks

—often used in plural