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.
Send a personal, handwritten note, a birthday card, or just a special email directly to them. Forbes.com, 4 June 2025 The story comes full circle with a twist: Eboni was able to give back to Ramona in a meaningful way, planning a surprise birthday party for her best friend. Ashley Vega, People.com, 4 June 2025 The last video on her account was posted hours before her murder, in which she was seen cutting a cake for her birthday. Saman Shafiq, USA Today, 4 June 2025 As Meghan Markle and Prince Harry continue to celebrate their daughter’s fourth birthday, Markle returned to Instagram to share a heartwarming video. Sara Vallone, Miami Herald, 4 June 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

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Cite this Entry

“Birthday.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/birthday. Accessed 10 Jun. 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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