birthday

noun

birth·​day ˈbərth-ˌdā 

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

Her birthday is September 30th.

Today is his 21st birthday.

The company just celebrated its 50th birthday.

Recent Examples on the Web

Pastore celebrated his 80th birthday last month at Daryl’s House, a restaurant and music club in upstate New York. — Julian Roberts-Grmela, New York Daily News, 1 Aug. 2026

Berry is currently on a tropical getaway in honor of her 60th birthday, which takes place on August 14. — Chanel Vargas, InStyle, 1 Aug. 2026

Indian producer and entrepreneur Viccky Jain has launched a new production banner, VJ Frames, timed to coincide with his birthday. — Naman Ramachandran, Variety, 1 Aug. 2026

His June birthday party was even a rave featuring music by Subtronics and Skrillex, both DJs. — Finnegan Belleau, Chicago Tribune, 1 Aug. 2026

Word History

First Known Use

14th century, in the meaning defined at sense 2

Phrases Containing birthday

• birthday suit

Rhymes for birthday

• airway
• allay
• archway
• array
• ashtray
• assez
• astray
• aue
• away
• ballet
• belay
• beltway

Kids Definition

birthday

noun

birth·​day ˈbərth-ˌdā 

1

: the day or anniversary of one's birth

2

: the day or anniversary of a beginning