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

She was the one who remembered birthdays, who called just to check in, who quietly carried more than she ever let on.

From BBC

He said they had no phones or credit cards, and added his birthday was on Christmas Day.

From BBC

The commemorations in Ashdown Forest to mark Pooh's 100th birthday are expected to include an installation, which would transform the forest's visitor centre into a life-sized pop-up book.

From BBC

“This doesn’t mean we should all be starting to worry the moment we have our birthday and we are suddenly 83 years old,” she says.

From The Wall Street Journal

Her daughter Ye-won, a cello instructor, had just celebrated her birthday and was due to return from a short holiday in Bangkok.

From Barron's