backside
noun [ C ] informal uk/ˈbæk.saɪd/ us/ˈbæk.saɪd/
(BODY)
屁股，臀部
the part of the body that you sit on
After cycling for the whole day, my backside was very sore. 骑了一整天自行车后，我的屁股很疼。
Synonym: bottom (BODY PART)
(BACK PART)
Indian English背面；后侧
the back part of something
On the backside of this building you will find a door. 在房子的后侧，你会看见一扇门。
Do not write anything on the backside of your answer book. 不要在答题本的背面写任何内容。
Idioms
a boot/kick up the/your backsideidiom UK very informal (US very informal a kick/boot in the/your backside) 鞭策，督促
the act of telling someone forcefully to start doing something more quickly or actively
She's so lazy - she needs a good boot up the backside. 她太懒了——需要有人好好督促一下。
get off your backsideidiom slang 起来干点儿活
to stop being lazy
Get off your backside and do some work! 起来干点儿活去！
sit (around) on your backsideidiom slang disapproving 无所事事
to do nothing
I do all the work, while all you do is sit around on your backside all day. 什么活都是我干，而你整天无所事事。