Definition of birthday in US English:



  • 1The anniversary of the day on which a person was born, typically treated as an occasion for celebration and the giving of gifts.

    as modifier ‘a birthday cake’
    ‘I'm getting a dollhouse for my birthday’
    ‘the birthday boy’
    • ‘It was Will's eighteenth birthday and he was spending the day with his friends and me.’
    • ‘I do remember his birthday, his wife's birthday, his two kids' birthdays, his anniversary and, of course, Christmas.’
    • ‘The husband of a friend of mine did this for her on her 30th birthday and she loved it!’
    • ‘If today is the first day of summer, then it must also be my baby sister's birthday.’
    • ‘Steve has made this cake on his birthday for his colleagues with an overwhelming positive response.’
    • ‘One thing was, there was a lot of talk about them flying the flag for Camilla's birthday.’
    • ‘Once we got there we all left to go to some local restaurant, for Lindsay's birthday.’
    • ‘He's just not happy with the poem I wrote for his wife's birthday, so he has to attack me.’
    • ‘You see my mother's birthday is coming up and I was thinking of getting one for her.’
    • ‘Bruce was also feted with a cake for his birthday which was one week before.’
    • ‘We visited the Polo Lounge for a friend's birthday last month and it was a real treat.’
    • ‘Today lardy cakes are served for birthdays or special occasions.’
    • ‘Katie and Kelly, now celebrating their 21st birthdays, were born ten weeks premature and were initially given a 50-50 chance of survival.’
    • ‘Apart from cakes on birthdays, few special foods are eaten at major secular ceremonies, although such ceremonies involve toasting and drinking alcohol.’
    • ‘Parents try to make their children's birthdays special with a cake, cards, and gifts.’
    • ‘The next time they saw each other was at Danielle's birthday party a couple of weeks later.’
    • ‘On our birthdays we have a cake and smiley-face stickers.’
    • ‘The three were going to talk about what they were going to do for Zack's birthday.’
    • ‘He would not miss another birthday or any other important moment in her life again.’
    • ‘Family and friends gathered around a huge birthday cake singing Happy Birthday.’
    1. 1.1 The day of a person's birth.
      ‘she shares a birthday with Paul McCartney’
      • ‘I was born on his birthday and the twelfth anniversary of his return to the throne.’
      • ‘The Blair baby would also share a birthday with Queen Victoria, who was born in 1819.’
      • ‘Others, who share their birthdays with the Queen Mother, arranged special parties themed around the big event.’
      • ‘As well as looking for people who share our birthday, we are keen to hear from anybody whose life has been touched by the paper.’
      • ‘Also we shared the same birthday.’
      • ‘My grandfather noted that the day I was born was also the birthday of Franklin Delano Roosevelt.’
      • ‘Here are a few prominent people that share their birthdays this month.’
      • ‘When Mrs Lee-Jones checked the dates she discovered that the two old girls' birthdays were just a day apart - Isobel's on March 2 and Lily's on March 3.’
      • ‘He said that every year since his schooldays people have pointed out that he shares his birthday with the prince.’
    2. 1.2 The anniversary of something starting or being founded.
      ‘the staff celebrated the twenty-fifth birthday of the paper’
      • ‘The Big Issue in Scotland will also celebrate its seventh birthday on 29 June.’
      • ‘Meanwhile, this Saturday is open day at the Hunt as the museum celebrates its seventh birthday.’
      • ‘London shares were slightly lower in a week that saw The Motley Fool celebrate its seventh birthday.’
      • ‘Google, celebrating its seventh birthday today, has revamped its video search service.’


  • in one's birthday suit

    • humorous Naked.

      • ‘I told her that despite it being cooler than usual… I'm still sleeping in my birthday suit.’
      • ‘At the prices these places charge I think you should be able to go round in your birthday suit if you want to.’
      • ‘I used to roll around in the snow in my birthday suit.’
      • ‘And a foxy new foreign exchange student strolls around school in her birthday suit.’
      • ‘However, if you do feel the need to run around in your birthday suit, then our advice would be to steer clear of Australia where such practices are met with a mandatory $5,000 fine.’
      • ‘I had to strip off and stand shivering in my birthday suit in calf-high water while she helped me wash.’
      • ‘I wanna walk around in my birthday suit.’
      • ‘No, I thought I would go down in my birthday suit.’
      • ‘A lone biker contributed to the day's entertainment when he rode past the crowd clad only in his birthday suit.’
      • ‘Women looked away and parents shielded their children's eyes as a foreigner with a receding hairline pranced on the New Delhi railway platform in his birthday suit.’