ephemeris

/ɪˈfɛməɹɪs/

//ɪˈfɛməɹɪs// noun

"ephemeris" is a 9-letter English headword indexed on PlainSpell.

The verdict

“ephemeris” is uncommon English (frequency #86,248 among 18,836 “E” headwords), classed as a noun. The kind of spelling people second-guess.

#86,248
frequency rank, English
18,836
“E” headwords

According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - A journal or diary.

Key facts for ephemeris
PropertyValue
Headwordephemeris
LanguageEnglish
Part of speechNoun
IPA/ɪˈfɛməɹɪs/
Letters9
Frequency rank#86,248
Misspellings tracked0
Confusable pairs0
SourceWiktionary (kaikki.org)

Where “ephemeris” 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). ephemeris lands here:

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

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

Rare enough to double-check

ephemeris is uncommon English at frequency #86,248 among 18,836 “E” headwords, classed as anoun, transcribed /ɪˈfɛməɹɪs/. Rarity is why readers land here mid-draft. 3 senses are on record.

ephemeris has no tracked misspelling variants, since its letter pattern doesn't lend itself to common typo substitutions. Our dataset records no confusable match here, which usually means its spelling is distinct enough that readers don't reach for a similar-looking word instead.

Etymologically, the entry records: From New Latin ephēmeris, from Ancient Greek ἐφημερίς (ephēmerís, “diary, calendar”), from ἐφήμερος (ephḗmeros, “daily”). The correct English form is ephemeris, spelled E-P-H-E-M-E-R-I-S.

Definition

  1. 1
    A journal or diary.
  2. 2
    A table giving the apparent position of celestial bodies throughout the year; normally given as right ascension and declination.
  3. 3
    Computer software that calculates the apparent position of celestial bodies.

Etymology

From New Latin ephēmeris, from Ancient Greek ἐφημερίς (ephēmerís, “diary, calendar”), from ἐφήμερος (ephḗmeros, “daily”).

This word in other languages

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 "ephemeris"?
"ephemeris" is spelled E-P-H-E-M-E-R-I-S. The IPA pronunciation is /ɪˈfɛməɹɪs/.
What does "ephemeris" mean?
As a noun, "ephemeris" means: A journal or diary.
How do you pronounce "ephemeris"?
The IPA (International Phonetic Alphabet) transcription for "ephemeris" is /ɪˈfɛməɹɪs/. 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 "ephemeris"?
From New Latin ephēmeris, from Ancient Greek ἐφημερίς (ephēmerís, “diary, calendar”), from ἐφήμερος (ephḗmeros, “daily”). 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 “ephemeris”

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

  • The one correct English spelling is E-P-H-E-M-E-R-I-S - every other letter order is a misspelling in standard orthography.
  • Say it as /ɪˈfɛməɹɪs/ (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

Other uncommon English words near this rank

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