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.
Recent Examples on the Web And speaking of their sweet kids, just last week, the couple revealed Tori had given birthday to their new baby! Good Housekeeping Editors, Good Housekeeping, 9 May 2022 Recipients of the $12,000 scholarships were selected Sunday on what would have been Arbery’s 28th birthday. Shaddi Abusaid, ajc, 9 May 2022 Ridgeway loved visiting Atlanta for Austin Williams' birthday and Atlanta Braves games. Eliott C. Mclaughlin, CNN, 8 May 2022 Sheeran celebrated Seaborn's 30th birthday with a rare tribute to his wife in May 2022. Savannah Walsh, ELLE, 7 May 2022 Tim shared another birthday tribute on his Instagram page. Katie Bowlby, Country Living, 7 May 2022 The Sussexes returned the following year to celebrate Meghan's birthday in the country. Emily Burack, Town & Country, 7 May 2022 That all three stayed in the game after their playing days ended speaks to what Bidwell taught them … Happy birthday to Adrian Gonzalez, who is 40. Peter Abraham,, 7 May 2022 Central to that will be a birthday parade, Trooping the Colour, and opportunities for Prince Harry and Meghan Markle to join the rest of the royal family in a series of celebrations. Simon Perry,, 7 May 2022 See More

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.

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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Dictionary Entries Near birthday

birth control pill


birthday cake

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Statistics for birthday

Last Updated

12 May 2022

Cite this Entry

“Birthday.” Dictionary, Merriam-Webster, Accessed 22 May. 2022.

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More Definitions for birthday


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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