The Chinese word 二氧化碳 (èryǎnghuàtàn, meaning "carbon dioxide") is formed through a logical, descriptive compounding of characters that directly reflects the chemical composition of the molecule: 二 (èr) means "two," 氧 (yǎng) means "oxygen," 化 (huà) indicates a compound or transformation (often used in chemical terms), and 碳 (tàn) means "carbon"; thus, the entire term transparently denotes a "carbon compound with two oxygen atoms."