birthday

American  

[burth-dey] / ˈbɜrθˌdeɪ /

noun

1. the anniversary of a birth.

2. the day of a person's birth.

3. a day marking or commemorating the origin, founding, or beginning of something.

4. the festivities or celebration marking such a day or anniversary.

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birthday British  

/ ˈbɜːθˌdeɪ /

noun

1. 1. an anniversary of the day of one's birth

   2. ( as modifier )

      birthday present

2. the day on which a person was born

3. any anniversary

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Etymology

Origin of birthday

Middle English word dating back to 1350–1400; birth, day

Example Sentences

“It’d be the ultimate 60th birthday present, right?” she said.

From Los Angeles Times • Apr. 4, 2026

On another Easter-related thread, a different commenter said: “We also throw in any leftover birthday favors and stocking stuffers.”

From MarketWatch • Apr. 2, 2026

A woman who was born without a womb and told she would not have children of her own went on to help deliver her biological son - who is about to celebrate his first birthday.

From BBC • Mar. 31, 2026

But “Austenland” is the latest installment in the BritBox celebration “Austen Forever,” and a film that represents the sentiments and inspiration for the months-long observance of the author’s 250th birthday last December.

From The Wall Street Journal • Mar. 31, 2026

My breath came short and hard as I thought back to the reports I had passed on, the night of Hitler’s birthday.

From "The Hiding Place" by Corrie ten Boom