birthday

noun

birth·​day ˈbərth-ˌdā How to pronounce birthday (audio)
1
a
: 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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Yet and The Real O'Neals, first met in 2019, when they were introduced at a mutual friends' 50th birthday party. Ryan Coleman, Entertainment Weekly, 27 Oct. 2025 Last October, the singer and songwriter indefinitely delayed her second studio album after her book of songs slated for the record were taken in a car theft just ahead of her birthday. Larisha Paul, Rolling Stone, 27 Oct. 2025 That December, Tavia put in a request for Swift's birthday present packaging. Zoey Lyttle, PEOPLE, 27 Oct. 2025 Avoid posting sensitive information like travel plans, birthdays or financial updates on social media. Kurt Knutsson, FOXNews.com, 14 Oct. 2025 See All Example Sentences for birthday

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

Browse Nearby Words

Cite this Entry

“Birthday.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/birthday. Accessed 29 Oct. 2025.

Kids Definition

birthday

noun
birth·​day ˈbərth-ˌdā How to pronounce birthday (audio)
1
: the day or anniversary of one's birth
2
: the day or anniversary of a beginning

More from Merriam-Webster on birthday

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