First Day

name

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

The verdict

“First Day” is outside the top-ranked English vocabulary, used as a proper noun - the kind of word writers most often double-check.

Unranked
below top-frequency English
9
letters

According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - Sunday (the first day of the Judeo-Christian seven day week).

Key facts for First Day
PropertyValue
HeadwordFirst Day
LanguageEnglish
Part of speechProper noun
Letters9
Misspellings tracked0
Confusable pairs0
SourceWiktionary (kaikki.org)

Where “First Day” sits in English frequency

First Day falls outside the top-100,000 ranked English words, the long-tail zone of technical, archaic, or low-frequency vocabulary, exactly where readers second-guess spellings most.

Beyond rank #100,000. Source: FrequencyWords open word-frequency list.

Spelling & Dictionary Insight

The English entry for First Day is 9 letters long, classified as a proper noun. It sits outside the most-frequent rank tiers, which is often why uncommon words generate more spelling variants per reader. The dominant gloss from Wiktionary reads: "Sunday (the first day of the Judeo-Christian seven day week).".

First Day doesn't appear in our generated misspelling index, since its letter sequence doesn't invite the usual edit-distance slips. Our dataset records no confusable match here, a sign it's visually distinctive enough not to be mixed up with another word.

Etymologically, the entry records: Used (like also First Month in place of January, etc) to avoid the pagan associations of the traditional name. The correct English form is First Day, spelled F-I-R-S-T- -D-A-Y.

Definition

  1. 1
    Sunday (the first day of the Judeo-Christian seven day week).

Etymology

Used (like also First Month in place of January, etc) to avoid the pagan associations of the traditional name.

Definitions, pronunciation, and etymology for this entry are drawn from Wiktionary via the kaikki.org structured extract (CC BY-SA). See the methodology for how each field is sourced and updated.

Frequently Asked Questions

How do you spell "First Day"?
"First Day" is spelled F-I-R-S-T- -D-A-Y.
What does "First Day" mean?
As a proper noun, "First Day" means: Sunday (the first day of the Judeo-Christian seven day week).
What is the origin of the word "First Day"?
Used (like also First Month in place of January, etc) to avoid the pagan associations of the traditional name. 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 “First Day”

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

  • The one correct English spelling is F-I-R-S-T- -D-A-Y - every other letter order is a misspelling in standard orthography.
  • 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