caffeine
US
UK caffeine n: (stimulant in tea and coffee)
SC 咖啡因 kā fēi yīn
SC 咖啡碱 kā fēi yīn，kā fēi jiǎn
Some people have a hard time waking up without a morning dose of caffeine.
caffeine-free, caffeine free adj: (without caffeine)
SC 不含咖啡因的，无咖啡因的 bù hán kā fēi yīn de，wú kā fēi yīn de