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

Some of his earlier memories are of dancing at family birthday parties or big public carnival events where the country’s top orchestras would play.

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

Many of them were asleep after celebrating till midnight at a birthday party.

From The Wall Street Journal • Apr. 1, 2026

They describe the details of their lives; practising yoga despite the sounds of explosions, eating birthday cake alone and venturing out to near-empty coffee shops.

From BBC • Mar. 31, 2026

“My birthday, I think? Maybe a little before.”

From "Keeping Pace" by Laurie Morrison