the anniversary of a birth.
the day of a person's birth.
a day marking or commemorating the origin, founding, or beginning of something.
the festivities or celebration marking such a day or anniversary.

Origin of birthday

Middle English word dating back to 1350–1400; see origin at birth, day Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for birthday

Contemporary Examples of birthday

Historical Examples of birthday

  • On the 24th of May we determined to celebrate the Queen's birthday.

  • In his sane moments he did not care a fig for anybody's birthday.


    William J. Locke

  • December 29, 1892, Mr. Gladstone celebrated his eighty-third birthday.

    The Grand Old Man

    Richard B. Cook

  • "He will not be here for his birthday," said Austin, in cold, even tones.


    William J. Locke

  • But before that came another feast,—their father's birthday.

    Rico and Wiseli

    Johanna Spyri

British Dictionary definitions for birthday



  1. an anniversary of the day of one's birth
  2. (as modifier)birthday present
the day on which a person was born
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

Word Origin and History for birthday

late 14c., from Old English byrddæg, "anniversary celebration of someone's birth" (at first usually a king or saint); see birth (n.) + day. Meaning "day on which one is born" is from 1570s. Birthnight is attested from 1620s.

Online Etymology Dictionary, © 2010 Douglas Harper