birthday

noun birth·day \ ˈbərth-ˌdā \
Updated on: 12 Nov 2017

Definition of birthday

1 a :the day of a person's birth
b :a day of origin
2 :an anniversary of a birth
  • her 21st birthday

Examples of birthday in a Sentence

  1. Her birthday is September 30th.

  2. Today is his 21st birthday.

  3. The company just celebrated its 50th birthday.

Recent Examples of birthday from the Web

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'birthday.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of birthday

14th century


BIRTHDAY Defined for English Language Learners

birthday

noun

Definition of birthday for English Language Learners

  • : the day when someone was born or the anniversary of that day

  • : the day when something began


BIRTHDAY Defined for Kids

birthday

noun birth·day \ ˈbərth-ˌdā \

Definition of birthday for Students

1 :the day or anniversary of someone's birth
2 :a day of beginning
  • Our town just celebrated its 150th birthday.


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to praise usually to excess

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