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.
In these places, led by regions like Sudan, Gaza, and South Sudan, children are three times more likely to die before their fifth birthday and 10 times more likely to grow up in extreme poverty than children born elsewhere. — David Miliband, Time, 19 Oct. 2026 Or to weather an economic emergency, or to stop modern slavery, or to combat unfair trade, or to stick it to a country that forgot to send the president a birthday gift. — Matthew Lynn, Washington Post, 19 Oct. 2026 Just a week ago, Kelce and Swift were celebrating the future Pro Football Hall of Famer’s 37th birthday while in New York City. — Scott Thompson Outkick, FOXNews.com, 19 Oct. 2026 Murders were ‘ice cold’ On the day of the murders, Sierra had joined the family on a shopping outing to Mall of the Americas to purchase a birthday gift for Daniela, who was days shy of turning 4. — Grethel Aguila, Miami Herald, 19 Oct. 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 20 Oct. 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
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