Example sentences
xiǎo小jiě姐，diǎn点cài菜。
Miss, we'd like to order.
nà那wèi位xiǎo小jiě姐hěn很piāo漂liàng亮。
That young lady is pretty.
About this word
小 means "small, young" and 姐 means "elder sister". 小姐 is literally "young elder sister", a family term that spread outward to any young woman. Today it works like "Miss": 王小姐, or on its own as 小姐. Be careful with it in mainland China, where it has picked up a seedy second meaning and can give offense. Service staff there are usually addressed as 服务员 or 美女. In Taiwan and much of the Chinese-speaking south, 小姐 stays a neutral, polite form.
The story behind the character
小
Three dots, like grains of sand. No story here. It just means tiny. Xu Shen wrote 小, 物之微也: "small, the slightness of things." Small enough to be a few specks.
姐
姐 is 女 (woman) with 且 on the right giving the sound. Xu Shen's entry is a small surprise: 姐，蜀謂母曰姐. In Shu, roughly modern Sichuan, this word meant mother. So 姐 started out as somebody's mom and drifted one generation down to older sister.