Dictionary.com
Thesaurus.com
Synonyms

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.


birthday British  
/ ˈbɜːθˌdeɪ /

noun

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

    2. ( as modifier )

      birthday present

  1. the day on which a person was born

  2. any anniversary

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of birthday

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

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.

Keep Reading on Vocabulary.com

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Yesterday, your sister’s birthday gift came from a Shopify store run by a kitchenware designer in Sacramento, California.

From Salon • May 27, 2026

Before putting the property on the market, Barrymore seized the opportunity to make at least one more core memory there, when she celebrated her 51st birthday with some of her closest friends.

From MarketWatch • May 27, 2026

It takes place on the US holiday of Flag Day -- which also happens to Trump's birthday.

From Barron's • May 26, 2026

His 80th birthday concert at New York’s Beacon Theater in 2010 was a critical success, but bronchial issues forced him into retirement in 2012.

From The Wall Street Journal • May 26, 2026

One time, during the Fourth of July when he was six years old, Pili had used her birthday money to buy a box of sparklers.

From "The Way to Rio Luna" by Zoraida Cordova

Vocabulary.com logo
by dictionary.com

Look it up. Learn it forever.

Remember "birthday" for good with VocabTrainer. Expand your vocabulary effortlessly with personalized learning tools that adapt to your goals.

Take me to Vocabulary.com