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.
Gregory Shamus/Getty Images Jenner, who just celebrated her 29th birthday on August 10, announced the non-pregnancy news in an interview with WhoWhatWear. — Marzia Nicolini, Vanity Fair, 29 Aug. 2026 Following the final bows by the cast, Parton received another surprise when a large tiered chocolate birthday cake was brought to the stage, wheeled out on one of the office desks used as part of the show. — Philip Potempa, Chicago Tribune, 28 Aug. 2026 That window begins either with their first year in college or the year following their 19th birthday, whichever comes first. — Jordan McPherson, Miami Herald, 28 Aug. 2026 In years prior, Jenner has celebrated her August birthday by planning lavish events, including luxury yacht excursions or renting out entire venues. — Sarah Glodek, Fortune, 28 Aug. 2026 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

Phrases Containing birthday

Rhymes for birthday

See All Rhymes for birthday

Browse Nearby Words

birth date
birthday
birthday cake
See all Nearby Words

Cite this Entry

“Birthday.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/birthday. Accessed 1 Sep. 2026.

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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
Last Updated: - Updated example sentences
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