birth·​day ˈbərth-ˌdā How to pronounce birthday (audio)
: the day of a person's birth
: a day of origin
: 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 Ahead of Ilaria Catalina Irena's first birthday, Hilaria shared on Sept. 7 an Instagram video montage of all the older six children off to their first day of school, with a brief appearance from baby Baldwin. Charna Flam, Peoplemag, 23 Sep. 2023 Swift’s birthday is Dec. 13; she’s made 13 her lucky number and a key symbol for her and her fans. Justine McDaniel, Washington Post, 22 Sep. 2023 And then, on my 16th birthday, Mom had an asthma attack. Trey Burnette, Los Angeles Times, 22 Sep. 2023 Despite the absence of stringent regulations, Swedes opted to cancel events like birthday parties, adopted remote working, and practiced physical distancing. Lars Jonung, National Review, 21 Sep. 2023 Philip Paxson was following Google Maps directions while driving home late at night in September 2022 from his daughter’s 9th birthday party when the navigation system directed him to go over an unmarked and unbarricaded bridge that had collapsed years prior, the suit filed Tuesday states. Jamiel Lynch, CNN, 21 Sep. 2023 In a neat little neighborhood in Venice, Calif., there’s a block of squat, similar homes, filled with mortals spending their finite days on the planet eating pizza with friends, blowing out candles on birthday cakes, and binging late-night television. Time, 20 Sep. 2023 In an Instagram grid post, the model, who shares her daughter with ex Zayn Malik, showed off bits and pieces of Khai’s birthday celebration, parties past, and moments together. Elizabeth Logan, Glamour, 20 Sep. 2023 What happened on the day Paxson died? Paxson and his wife, Alicia Paxson, had originally planned for a birthday camping trip for their daughter, but came up with alternative plans because of a storm. Aliza Chasan, CBS News, 20 Sep. 2023 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'birthday.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

14th century, in the meaning defined at sense 2

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

Dictionary Entries Near birthday

Cite this Entry

“Birthday.” Dictionary, Merriam-Webster, Accessed 30 Sep. 2023.

Kids Definition


birth·​day ˈbərth-ˌdā How to pronounce birthday (audio)
: the day or anniversary of one's birth
: the day or anniversary of a beginning

More from Merriam-Webster on birthday

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