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

“The fact that Dakota did this to the mother of his child on his child’s birthday tells you everything you need to know about Dakota,” he said.

From Los Angeles Times

His best-known innovation—his introduction, in 1922, of the modern bat mitzvah, to mark the 12th birthdays of Jewish girls—is now standard practice in all but Orthodox synagogues.

From The Wall Street Journal

As Apple marks its 50th birthday on April 1, it’s a timely moment to revisit the legendary Jobs demo.

From Los Angeles Times

Places left and right — colleges, cities, classrooms, even states that mark Chávez’s birthday as a holiday — are now deleting his name and image from the public sphere.

From Los Angeles Times

Biles, who turned 29 on March 14, revealed that she was spending the start of her birthday week at home in Texas, where she snapped several photos of the dwelling.

From MarketWatch