birth·​day | \ ˈbərth-ˌdā How to pronounce birthday (audio) \

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 Reyna and Musah became just the 12th and 13th Americans to make an appearance before turning 18 (Reyna's 18th birthday was Friday). USA TODAY, "How to watch U.S. men's soccer team vs. Panama: TV channel, live stream, start time, USMNT roster," 16 Nov. 2020 Raise a glass to the artist Georgia O’Keeffe, whose birthday was Sunday. Adriana Balsamo, New York Times, "Cook Up Some Scallion Pancakes or Horror Stories," 14 Nov. 2020 Held at Randolph in celebration of the first birthday of an independent Air Force, the 1948 air show would bring in personnel from other area Air Force installations: Brooks, Kelly and Lackland. Paula Allen,, "Air shows keep San Antonio looking up to local military," 14 Nov. 2020 His birthday is the exact same date as our son, Henry (June 14). cleveland, "Welcoming Benji, a special puppy with the heart of an angel: Send us your pet rescue stories," 12 Nov. 2020 Harford County government held a flag-raising ceremony on Tuesday morning, recognizing employees who are veterans of the U.S. military and the 245th birthday of the U.S. Marine Corps. Aegis Staff,, "Harford County honors veterans, salutes Marine Corps 245th birthday with flag raising ceremony," 10 Nov. 2020 In celebration of the 100th birthday of Pompano’s own Esther Rolle, the public is invited to a special Live on the Set virtual celebration of her life and legacy with BernNadette Stanis. Mary Lou Cruz,, "Calendar: Virtual community, entertainment events beginning Nov. 4," 2 Nov. 2020 One name, Emmett Till, stuck out for me — because his birthday was exactly the same as mine, July 25, 1941. Ed Stockly, Los Angeles Times, "Feedback: White privilege in art museums runs deep," 1 Nov. 2020 Poston's account listed the same birthday as Griffie's, and Griffie's Bureau of Motor Vehicles photo and information also matched Galle's description of Poston, the affidavit said. Lawrence Andrea, The Indianapolis Star, "Indianapolis man faces murder, other charges in killing of man and shooting of woman," 26 Oct. 2020

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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Time Traveler for birthday

Time Traveler

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

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Statistics for birthday

Last Updated

19 Nov 2020

Cite this Entry

“Birthday.” Dictionary, Merriam-Webster, Accessed 26 Nov. 2020.

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More Definitions for birthday


How to pronounce birthday (audio)

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 How to pronounce birthday (audio) \

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.

More from Merriam-Webster on birthday

Nglish: Translation of birthday for Spanish Speakers

Britannica English: Translation of birthday for Arabic Speakers

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