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.
But in following his friend and fellow war journalist, the titular Osama Al-Ashi, over a single year from the birth of his son in mid-2024 to his first birthday, Hassouna accomplishes something not many filmmakers set out to. — Ritesh Mehta, IndieWire, 5 Sep. 2026 Her birthday also coincided with the 20th anniversary of her hit album B’Day. — Angel Saunders, PEOPLE, 5 Sep. 2026 In a blurred photo from his last birthday party, he is seen in front of a giant cake with the number 89 drawn in blue and red frosting. — Nora Gámez Torres, Miami Herald, 5 Sep. 2026 Trump’s botched repairs to the Reflecting Pool ahead of the nation’s 250th-birthday celebrations, in July, offer a classic example of the problem. — Janay Kingsberry, The Atlantic, 5 Sep. 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 7 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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