1610s, "upper side or surface," from up (adj.) + side (n.). Adverbial phrase upside (someone's) head in reference to a blow to the head is recorded from 1970, U.S. black slang.
权威例句
1. Salter held the bag by the corners and shook it upside down.
索尔特捏住包的外角,把它倒过来晃了晃。
2. Tony had an upside-down map of Britain on his wall.
托尼的墙上倒挂了一张英国地图。
3. The lid, turned upside down, served as a coffee table.
那个盖子被翻过来当作咖啡桌。
4. His eyes were open and everything he saw was upside down.