birthday

American  

[burth-day] / ˈbɜrθˌdeɪ /

noun

• birthdays
  plural

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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Other Word Forms

Noun Inflected Forms

• birthdays
  plural

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Etymology

Origin of birthday

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

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Explanation

Your birthday is the day of your birth! It’s the yearly anniversary that marks the day you were born. Not everyone celebrates, but a birthday is a good excuse for a party and cake. You can use birthday both to refer to the specific day of a baby's birth, and the annual marking of that day throughout the years that follow. Sometimes people talk about the birthday of a country, group, or even a building: "It's the art museum's fiftieth birthday next year." The Old English byrddæg originally referred to the celebration of a king or saint's birth, but over the years it was extended to include everyone.

Example Sentences

See Examples For:

birthday birthdays

Atlanta native John Perez celebrated his 28th birthday at Zoo Atlanta on Friday, telling AFP the pandas drew him to visit for the first time because "it felt perfect, you know?"

From Barron's ● Nov. 7, 2026

Jack, who was not called into the England team until days before his 30th birthday, won 35 caps.

From BBC ● Nov. 6, 2026

In California, they already are allowed to preregister to vote so that on their 18th birthday, they become automatically eligible to cast a ballot.

From Los Angeles Times ● Nov. 5, 2026

“This is like Christmas and a birthday and an Easter bunny and Halloween!” he said.

From Salon ● Nov. 4, 2026

Mom’s birthday comes and goes with no sign of Jonah.

From "Red Flags and Butterflies" by Sheryl Azzam

On the night I went, two parties were celebrating birthdays.

From The Wall Street Journal ● Oct. 25, 2026

The law, which took effect in 2012, allowed a limited number of children with fall birthdays to attend a full year of school before kindergarten, called transitional kindergarten.

From Los Angeles Times ● Oct. 22, 2026

Volunteer bakers are paying out of their own pockets so children in need do not go without a cake on their birthdays.

From BBC ● Sep. 30, 2026

While some teenagers may mark their 18th birthdays by buying a lottery ticket or getting a first tattoo, Deon Radcliff Jr. had different priorities.

From MarketWatch ● Sep. 24, 2026

I was only fifty-one then, and birthdays did not seem so important.

From "The Fellowship of the Ring" by J.R.R. Tolkien

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