birth·day | \ˈbərth-ˌdā \

Definition of birthday 

1a : the day of a person's birth

b : a day of origin

2 : an anniversary of a birth her 21st birthday

Examples of birthday in a Sentence

Her birthday is September 30th. Today is his 21st birthday. The company just celebrated its 50th birthday.
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Recent Examples on the Web

January 2016: Horsing Around Oklahoma native Shelton gives Stefani a horse for her birthday. Sofia Mele, Billboard, "A Timeline of Gwen Stefani & Blake Shelton's Relationship," 11 July 2018 And my girlfriend made me this dope jacket for my birthday with safety pins on it and a skull in the back with some crazy eyes and cheetah print lining on the inside. Jamie Lisanti,, "Fashionable 50," 10 July 2018 The statue was a present from Richardson's former team partners in 2016 for his 80th birthday. Scott Fowler, charlotteobserver, "Jerry Richardson's parting gift to fans, David Tepper: A statue of limitations," 10 July 2018 For his 6th birthday in March, Madden’s godmother got him an atlas. Allie Caren, Washington Post, "Meet the 6-year-old who can name every country — in alphabetical order," 5 July 2018 In the first Toy Story movie, Andy gets a lunch box for his birthday. Megan Friedman, Good Housekeeping, "Toy Story Land Is Riddled With Amazing Hidden References to the Movies," 2 July 2018 Joey was recently in Vancouver visiting her boyfriend and The Kissing Booth co-star, Jacob Elordi, for his birthday. Tamara Fuentes, Seventeen, "Joey King and Sabrina Carpenter Perform EPIC "High School Musical" Throwback Together," 28 June 2018 Last week, the Flip or Flop star surprised his employee with a luxury car for her birthday, and of course, some followers were quick to read into the generous gift. Taysha Murtaugh, Country Living, "Yes, Tarek El Moussa Bought His Kids' Nanny a Car. No, He Is Not Dating Her.," 19 June 2018 On Saturday night, West capped his last heady weeks with a 41st birthday party with his family and a small town’s worth of friends, from Pusha T to Teyana Taylor to Twitter’s Jack Dorsey. Emma Stefansky, Vanities, "Rick and Morty, a Mountain Cake, and Jack Dorsey: Inside Kanye West’s 41st Birthday Party," 10 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'birthday.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of birthday

14th century, in the meaning defined at sense 2

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Statistics for birthday

Last Updated

15 Oct 2018

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Time Traveler for birthday

The first known use of birthday was in the 14th century

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More Definitions for birthday



English Language Learners Definition of birthday

: the day when someone was born or the anniversary of that day

: the day when something began


birth·day | \ˈbərth-ˌdā \

Kids Definition of birthday

1 : the day or anniversary of someone's birth

2 : a day of beginning Our town just celebrated its 150th birthday.

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Comments on birthday

What made you want to look up birthday? Please tell us where you read or heard it (including the quote, if possible).


to reject or criticize sharply

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