Word: 咖啡因 (kāfēiyīn) 咖啡因 dictionary entry kāfēiyīn caffeine (loanword) Full dictionary entry for 咖啡因 Example sentences using 咖啡因 2 sentences, showing page 1 of 1. 咖啡因摄入过多会睡不着。 Kāfēiyīn shèrùguo duō huì shuì bù zháo. Too much caffeine consumption can keep you from sleeping. 咖啡里的咖啡因也是一种兴奋剂。 Kāfēi lǐ de kāfēiyīn yě shì yìzhǒng xīngfènjì. The caffeine in coffee is also a kind of stimulant.