Example sentences
nǐ你mǎi买shén什me么dōng东xī西？
What are you buying?
dōng东xī西fàng放zhè这ér儿。
Put the stuff here.
About this word
东 is "east" and 西 is "west". Read as dōngxī it means the two directions, but with a neutral second syllable, dōngxi, it means "thing, stuff", and the tone change is what marks the jump from the literal pair to the noun. Pairing opposites to cover a range is a common move in Chinese: 大小 covers size, 长短 covers length, 多少 covers quantity. A popular explanation traces the "stuff" sense to the two markets of the Tang capital, but the word itself shows only the two directions. In casual speech 东西 can also insult a person.
The story behind the character
东
The traditional 東 is 日 (sun) caught in the middle of 木 (tree). The sun rising through the trees. That direction is east. Xu Shen wrote 东, 动也: "to stir," because when the sun rises, everything stirs.
西
西 was once a bird's nest. The earliest form is a nest, and it meant "to roost". A bird settling in for the night. Then it got borrowed for "west," and people had to coin a new 栖 for roosting. So 西 wasn't a direction; it was a bird's nest.