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” has 13 generated spelling variants in the English index at frequency #1,783. The variants make it a useful spelling check.

#1,783
frequency rank, English
4,121
“B” headwords
13
tracked misspellings

According to Wiktionary data (CC BY-SA, analyzed September 3, 2026) - The anniversary of the day on which someone is born.

Corpus desk

Index EN-birthday · birthday · English

birthday · rank #1,783 · 13 variants · 0 confusables

  • FREQ-COMMON #1,783
  • LEN-LONG 8 letters
  • VOW-3 3 vowels
  • CONFUS-0 No pairs
  • VAR-HIGH 13 variants
  • BOOK-MID 4,121
  • PHOTO-FINISH balance

Nearest frequency peer: balance (-1 rank slots)

Read with this headword: Spelling guide for this pattern

Desk codes from Wiktionary headword shape, FrequencyWords rank tier, confusable-pair count, generated misspelling depth, letter-cohort book size, and photo-finish peer. Not a difficulty grade.

Rank peers near misspelling magnet “birthday”

Same rarity band: useful when a typo lands on a peer headword

corpus weight

What this shows “birthday” sits among these FrequencyWords peers; misspelling depth is tracked separately in the edit-distance chart.

Source FrequencyWords open word-frequency list As of September 3, 2026
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)

Frequency seat of misspelling magnet “birthday”

Word frequency stretches from the small set of words we reach for constantly (left) out to the long tail barely used once in a while (right).birthdaylands here:

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

Scale is logarithmic (each tick is 10× rarer). Same rarity band neighbours include “balance” (#1,782), “bitch” (#1,784), “apple” (#1,781). Among 4,121 “B” headwords, “birthday” is #1,783. Source: FrequencyWords open word-frequency list.

A misspelling magnet

The generator records 13 spelling variants around birthday (IPA /ˈbɜːθ.deɪ/), anoun. Corpus frequency is #1,783 among 4,121 “B” headwords. Wiktionary lists 4 senses, so context still picks the gloss.

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.

Recorded use

Wiktionary examples

These source excerpts show how birthday appears in context. They illustrate usage; the definition above remains the entry’s reference meaning.

  1. When's your birthday? Mine's on April 1.
  2. I'll be thirty-seven (years old) next birthday.

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.

Similar English words by spelling shape

Same letter count and similar misspelling depth for "birthday", not the corpus desk frequency band.

Same letter count

Frequency-ranked English headwords with 8 letters (nearest by frequency rank).

changing#1,787software#1,775possibly#1,770believed#1,810

Similar misspelling depth

Headwords with a similar count of attested misspellings (13 here; floor ≥5).

operating13 variantsmaterials13 variantsthoughts13 variantsfunction13 variants

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

Source: FrequencyWords open word-frequency list