birthday

/ˈbɜːθ.deɪ/

//ˈbɜːθ.deɪ// noun

By · According to Wiktionary data (CC BY-SA) ·

"birthday" is a 8-letter English headword indexed on PlainSpell.

The verdict

“birthday” is a regularly-used English word, ranked #1,783 in English word frequency and used as a noun.

#1,783
frequency rank, English
8
letters
13
tracked misspellings

According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - The anniversary of the day on which someone is born.

Key facts for birthday
PropertyValue
Headwordbirthday
LanguageEnglish
Part of speechNoun
IPA/ˈbɜːθ.deɪ/
Letters8
Frequency rank#1,783
Misspellings tracked13
Confusable pairs0
SourceWiktionary (kaikki.org)

Where “birthday” sits in English frequency

Every-word frequency runs from the handful of words we use constantly (left) to the long tail used once in a blue moon (right). birthday lands here:

#1#100#1K#10K#100K
← used constantlyrarely used →

Scale is logarithmic (each tick is 10× rarer). Source: FrequencyWords open word-frequency list.

Spelling & Dictionary Insight

The English entry for birthday is 8 letters long, classified as a noun, and transcribed in the International Phonetic Alphabet as /ˈbɜːθ.deɪ/. Corpus data places it at rank #1,783 in overall English word frequency, indicating it appears regularly in written and spoken text. Wiktionary records 4 distinct senses for this headword, so context determines which meaning a reader should apply.

Our generated misspelling index lists 13 likely wrong-spelling variants for birthday, with forms such as "bbirthday", "birhtday", and "birrthday". Each of these forms differs from the correct spelling by one small edit: a doubled letter, a dropped silent letter, or a substituted vowel. This headword has no recorded confusable partner, since nothing in our dataset looks or sounds close enough to cause mix-ups.

Etymologically, the entry records: From Middle English birthdai, birtheday, from Old English ġebyrddæġ (“birthday”), influenced by Old Norse burðr, equivalent to birth + day. Compare Saterland Frisian Gebuursdai (“birthday”), Dutch geboortedag (“birthday”), Low German Geboortsdag (“birthday”… The correct English form is birthday, spelled B-I-R-T-H-D-A-Y.

Definition

  1. 1
    The anniversary of the day on which someone is born.
  2. 2
    The anniversary of the day on which something is created.
  3. 3
    The date on which someone is born or something is created, more commonly called birthdate or date of birth.
  4. 4
    A birthday party.

Etymology

From Middle English birthdai, birtheday, from Old English ġebyrddæġ (“birthday”), influenced by Old Norse burðr, equivalent to birth + day. Compare Saterland Frisian Gebuursdai (“birthday”), Dutch geboortedag (“birthday”), Low German Geboortsdag (“birthday”), German Geburtstag (“birthday”), Norwegian bursdag, gebursdag (“birthday”). Eclipsed non-native Middle English nativitee (“birth, nativity, birthday”), from Old French nativité, nativited, from Latin nātīvitas.

This word in other languages

cumpleaños(Español)anniversaire(Français)Geburtstag(Deutsch)aniversário(Português)

Common misspellings

Also misspelled as: bbirthday,birhtday,birrthday,birtdhay,birthady,birthdayy,birthdday,birthdya,birthhday,birtthday,bitrhday,brithday,ibrthday

Misspelling Pattern Breakdown

How far each generated variant is from the correct spelling of birthday - counted as single-character edits (an insertion, a deletion, or a substituted letter). The larger the bar, the easier the typo is to spot; one-edit slips are the ones that sneak past readers.

bbirthday1birhtday2birrthday1birtdhay2birthady2birthdayy1birthdday1birthdya2
Edit distance from "birthday"

Definitions, pronunciation, and etymology for this entry are drawn from Wiktionary via the kaikki.org structured extract (CC BY-SA); frequency ordering uses the FrequencyWords open word-frequency list (2018 English corpus, MIT). See the methodology for how each field is sourced and updated.

Frequently Asked Questions

How do you spell "birthday"?
"birthday" is spelled B-I-R-T-H-D-A-Y. The IPA pronunciation is /ˈbɜːθ.deɪ/.
What does "birthday" mean?
As a noun, "birthday" means: The anniversary of the day on which someone is born.
What are common misspellings of "birthday"?
Common misspellings include "bbirthday", "birhtday", "birrthday", "birtdhay", "birthady". The correct spelling is "birthday".
How do you pronounce "birthday"?
The IPA (International Phonetic Alphabet) transcription for "birthday" is /ˈbɜːθ.deɪ/. Click the speaker icon on the pronunciation badge above to hear it spoken aloud where audio is available.
What is the origin of the word "birthday"?
From Middle English birthdai, birtheday, from Old English ġebyrddæġ (“birthday”), influenced by Old Norse burðr, equivalent to birth + day. Compare Saterland Frisian Gebuursdai (“birthday”), Dutch geboortedag (“birthday”), Low German Geboortsdag (... See the full etymology section above for more details.
Is PlainSpell free to use?
Yes, PlainSpell is a completely free word reference. You can look up definitions, pronunciations, confusable pairs, homophones, and spelling corrections across 5 languages without any sign-up or subscription.

Using “birthday”

The practical upshot for anyone who landed here from a spell-check.

  • The one correct English spelling is B-I-R-T-H-D-A-Y - every other letter order is a misspelling in standard orthography.
  • Say it as /ˈbɜːθ.deɪ/ (IPA); tap the speaker on the pronunciation badge to hear it where audio exists.
  • Browse more English words and confusable pairs in the same reference. English words
Data Source

Wiktionary (via kaikki.org), licensed under CC BY-SA & GFDL. Word ordering uses an open word-frequency list; misspelling variants are generated by edit-distance from the correct headword.

Source: Wiktionary (via kaikki.org) Structured Wiktionary extract

Source: FrequencyWords open word-frequency list FrequencyWords open word-frequency list