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

On his 82nd birthday, Halas was asked by the Tribune’s David Condon to name his all-time Bears team for his Feb. 2, 1977, column. Will Larkin,, "Ranking the 100 best Bears players ever: No. 77, Bill Osmanski," 21 June 2019 On his eighth birthday, he was presented with a general's uniform, complete with gold buttons and epaulets and things. CBS News, "Transcript: Anna Fifield talks with Michael Morell on "Intelligence Matters"," 19 June 2019 Rather than be upset with her for being honest with you, respect her wishes and on her birthday, send her a card. Abigail Van Buren, Twin Cities, "Dear Abby: Sports fan’s mania leaves little time for relationships," 17 June 2019 Early on in his tenure, McFaul started asking for cash donations from employees on his birthday and Christmas, the report said. Robert Higgs,, "Opponents of plan to return to elected Cuyahoga County sheriff stir memories of the corrupt days of Gerald McFaul," 17 June 2019 Rather than be upset with her for being honest with you, respect her wishes and on her birthday, send her a card. Dear Abby,, "Dear Abby: Sports fanatic boyfriend has time for the games, not the girl," 17 June 2019 On his 49th birthday, Phil Mickelson, the five-time major winner, shot one-over 72 ito finish the Open at four over. Sam Farmer And Tod Leonard,, "U.S. Open notes: Viktor Hovland’s performance was no amateur hour," 16 June 2019 On his 49th birthday, the five-time major winner shot 1-over 72 in the final round to finish at 4 over. San Diego Union-Tribune, "Schauffele posts another high finish in major," 16 June 2019 My first child, my beautiful, tender daughter Parker died of incurable cancer just days before her first birthday. Jon Caldara, The Denver Post, "Caldara: Colorado is ready for a reasonable abortion debate," 14 June 2019

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

25 Jun 2019

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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 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.

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More from Merriam-Webster on birthday

Rhyming Dictionary: Words that rhyme with birthday

Spanish Central: Translation of birthday

Nglish: Translation of birthday for Spanish Speakers

Britannica English: Translation of birthday for Arabic Speakers

Comments on birthday

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having a desire to acquire more things

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