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 my 33rd birthday, friends from hither and yon e-mailed best wishes for my Jesus year, an allusion to Christ's earthly life span. Hamilton Cain Special To The Star Tribune, Star Tribune, "Review: 'The Five Wounds,' by Kirstin Valdez Quade," 2 Apr. 2021 My partner also surprised me with my very own blue vintage Schwinn on my 26th birthday. Dana Heyward, Bon Appétit, "Learning to Ride a Bike Eased My Chronic Anxiety," 31 Mar. 2021 Sánchez made his major league debut on his 22nd birthday last year and went 3-1 with a 1.69 ERA in his first five starts. Steven Wine,, "Season preview: Young Marlins look to build on surprising 2020 playoff run," 30 Mar. 2021 Making things more difficult, the singer ended up getting cut on his birthday. Kayla Keegan, Good Housekeeping, "'American Idol' Fans Have "Never Been So Upset" After Judges Make a "Huge" Top 24 Mistake," 29 Mar. 2021 Colin Blackwell scored twice on his 28th birthday, No. 1 pick Alexis Lafrenière scored the fifth goal of his rookie season and Chris Kreider scored on the power play, cutting New York’s deficit to one with 3:52 left. Stephen Whyno,, "Rangers’ four-goal third not enough to overtake Capitals, who get 10th win in 11 games," 28 Mar. 2021 This week, Panettiere gave a shout-out to Klitschko on Instagram, posting a tribute to the Ukrainian boxing champ on his 45th birthday. Jodi Guglielmi,, "Hayden Panettiere Is in a 'Wonderful Headspace' After Turbulent Few Years: Source," 26 Mar. 2021 So, on his 35th birthday, Lowry woke up as a Raptor — and remained one. Tim Reynolds, ajc, "Trade deadline passes, and Kyle Lowry remains with Raptors," 25 Mar. 2021 Marlen Mora-Gomez, a junior at Reagan High School, got a COVID-19 vaccine on her 17th birthday Monday at South Division High School. Rory Linnane, Milwaukee Journal Sentinel, "Estimates suggest at least a third of those 16 and older qualify for vaccine. Here's how.," 25 Mar. 2021

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

6 Apr 2021

Cite this Entry

“Birthday.” Dictionary, Merriam-Webster, Accessed 17 Apr. 2021.

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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.

More from Merriam-Webster on birthday

Nglish: Translation of birthday for Spanish Speakers

Britannica English: Translation of birthday for Arabic Speakers

Comments on birthday

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