equinox

/ˈɛkwɪnɒks/

//ˈɛkwɪnɒks// noun

"equinox" is a 7-letter English headword indexed on PlainSpell.

The verdict

“equinox” has 9 generated spelling variants in the English index at frequency #28,191. The variants make it a useful spelling check.

#28,191
frequency rank, English
18,836
“E” headwords
9
tracked misspellings
1
confusable pair

According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - One of two times in the year (one in March and the other in September) when the length of the day and the night are equal, which occurs when the sun is directly overhead at the equator; this marks ...

Visual similarity to commonly confused words

How many letter changes separate each confused pair (Levenshtein distance, normalized).

equinox vs equine
71% similar

Source: PlainSpell confusable corpus (Wiktionary, CC BY-SA).

Key facts for equinox
PropertyValue
Headwordequinox
LanguageEnglish
Part of speechNoun
IPA/ˈɛkwɪnɒks/
Letters7
Frequency rank#28,191
Misspellings tracked9
Confusable pairs1
SourceWiktionary (kaikki.org)

Where “equinox” 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). equinox lands here:

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

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

A misspelling magnet

The generator records 9 spelling variants around equinox (IPA /ˈɛkwɪnɒks/), anoun. Corpus frequency is #28,191 among 18,836 “E” headwords. Wiktionary lists 5 senses, so context still picks the gloss.

Our generated misspelling index lists 9 likely wrong-spelling variants for equinox, with forms such as "eqiunox", "eqquinox", and "equinnox". Every one of these variants traces to a single-character edit -- an added or dropped letter, a swapped consonant, or a vowel swap -- the kind of slip a spell-checker is built to catch. It also participates in 1 confusable-pair relationship, "equine", since the words sound or look close enough that writers reach for the wrong one mid-sentence.

Etymologically, the entry records: PIE word *nókʷts From Middle English equinox, equinoxe, equynox (“one of the two periods in the year when the day and night are of equal length, equinox; either the zodiac sign Aries or Libra, in which the sun crosses the celestial equator”), from Old Fren… The correct English form is equinox, spelled E-Q-U-I-N-O-X.

Definition

  1. 1
    One of two times in the year (one in March and the other in September) when the length of the day and the night are equal, which occurs when the sun is directly overhead at the equator; this marks the beginning of spring in one hemisphere and autumn in the other.
  2. 2
    The circumstance of a twenty-four hour time period having the day and night of equal length.
  3. 3
    One of the two points in space where the apparent path of the Sun intersects with the equatorial plane of the Earth.
  4. 4
    A gale (“very strong wind”) once thought to occur more frequently around the time of an equinox (sense 1), now known to be a misconception; an equinoctial gale.
  5. 5
    A celestial equator (“great circle on the celestial sphere, coincident with the plane of the Earth's equator (the equatorial plane)”); also, the Earth's equator.

Etymology

PIE word *nókʷts From Middle English equinox, equinoxe, equynox (“one of the two periods in the year when the day and night are of equal length, equinox; either the zodiac sign Aries or Libra, in which the sun crosses the celestial equator”), from Old French equinoce, equinoxe (modern French équinoxe), or from its etymon Medieval Latin ēquinoxium, ēquinoctium, from Latin aequinoctium (“equinox”), from aequus (“equal”) + nox (“night”) (ultimately derived from Proto-Indo-European *nókʷts (“night”)) + -ium (suffix forming abstract nouns). The Latin word, ultimately adopted in Middle English and modern English, displaced Old English efnniht (modern English evennight). The rare alternative plural form equinoctes treats equinox as if it were a Latin word; the plural of Latin nox (“night”) is noctēs.

This word in other languages

Common misspellings

Also misspelled as:

  • eqiunox
  • eqquinox
  • equinnox
  • equinoxx
  • equinxo
  • equionx
  • equniox
  • euqinox
  • qeuinox

Misspelling Pattern Breakdown

How far each generated variant is from the correct spelling of equinox - expressed in single-character edits (insert, delete, or swap one letter). Bigger bars stand out at a glance; a one-edit slip is the hardest to catch.

eqiunox2eqquinox1equinnox1equinoxx1equinxo2equionx2equniox2euqinox2
Edit distance from "equinox"

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 "equinox"?
"equinox" is spelled E-Q-U-I-N-O-X. The IPA pronunciation is /ˈɛkwɪnɒks/.
What does "equinox" mean?
As a noun, "equinox" means: One of two times in the year (one in March and the other in September) when the length of the day and the night are equal, which occurs when the sun is directly overhead at the equator; this marks ...
What words are commonly confused with "equinox"?
"equinox" is commonly confused with "equine". These words look or sound similar but have different meanings. PlainSpell provides detailed comparisons for each pair.
How do you pronounce "equinox"?
The IPA (International Phonetic Alphabet) transcription for "equinox" is /ˈɛkwɪnɒks/. 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 "equinox"?
PIE word *nókʷts From Middle English equinox, equinoxe, equynox (“one of the two periods in the year when the day and night are of equal length, equinox; either the zodiac sign Aries or Libra, in which the sun crosses the celestial equator”), fro... 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 “equinox”

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

  • The one correct English spelling is E-Q-U-I-N-O-X - every other letter order is a misspelling in standard orthography.
  • Say it as /ˈɛkwɪnɒks/ (IPA); tap the speaker on the pronunciation badge to hear it where audio exists.
  • Don't mix it up with “equine” - see the side-by-side comparison. equinox vs equine
  • Browse more English words and confusable pairs in the same reference. English words

Same frequency band

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