birthday/'bɜːθdeɪ $ 'bɜːrθ-/

n. the day that is exactly a year or number of years after a person was born

n. [C] 生日：Happy birthday! 生日快乐！

◇a birthday card/gift/party生日卡片/礼物/派对

◇Bill celebrated his 15th birthday three days ago. 比尔3天前过了15岁生日。

构词birth + day

同根 holiday; weekday; workday

用法birthday和birth date （= date of birth出生日期）不同，如：Her birth date was May 5, 1988. 她的出生日期是1988年5月5日。