sidereal
/saɪˈdɪɚ.i.əl/adjective
sidereal is spelled S-I-D-E-R-E-A-L: 8 letters and 4 syllables. It appears about once in every 6 million words in written English, the 74,122nd most frequent word form (wordfreq, 2021 data). As an adjective, sidereal means “Of or relating to the stars” (English Wiktionary, September 2026).
How many letters and syllables are in sidereal?
| Letters | 8: S-I-D-E-R-E-A-L |
|---|---|
| Syllables | 4 (from its pronunciation) |
| In writing | about once in every 6 million words; the 74,122nd most frequent word form |
| Wrong spellings searched | none measured in search |
| Rhymes with |
Sources: letters and syllables from the English Wiktionary's hyphenation or pronunciation; written frequency: wordfreq 3.1 (a 2021 snapshot of Wikipedia, subtitles, news, books, web text and social media); rhymes and same-letter words are computed by PlainSpell from its own word list.
How common is sidereal?
Sidereal appears about once in every 6 million words in written English, the 74,122nd most frequent word form in the list.
Source: written frequency: wordfreq 3.1 (a 2021 snapshot of Wikipedia, subtitles, news, books, web text and social media).
How do you pronounce sidereal?
- UK /saɪˈdɪə.ɹi.əl/
- US /saɪˈdɪɚ.i.əl/
- US /sɪˈdɪɚ.i.əl/
Sidereal has 4 syllables (counted from the pronunciation).
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract). Recordings: En-us-sidereal.ogg, En-us-sidereal_2.ogg, Wikimedia Commons (author and licence on each file's page).
What rhymes with sidereal?
One word on PlainSpell end in the same sounds as sidereal from its last stressed vowel (/ɪəɹiəl/):
Computed by PlainSpell from the pronunciations in the English Wiktionary (dump of September 2, 2026): a rhyme shares every sound from the last stressed vowel to the end; ordered by written frequency (wordfreq 3.1).
Forms of sidereal
- sideral
- sidaereal
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract).
What does sidereal mean?
The meanings the English Wiktionary records, quoted as written there (source below).
adjective
- 1
Of or relating to the stars.
- 2
Relating to a measurement of time relative to the position of the stars.
- 3
Relating to a measurement of time relative to the point of the vernal equinox.
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract).
Sidereal in Spanish, French, German and Portuguese
In the sense of or relating to the stars:
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract). Translations are Wiktionary's, by sense; a linked word has its own PlainSpell page.
Where does sidereal come from?
From Latin sīdereus + -al (cf. Latin sīderālis), from sīdus (“star, constellation”), of unknown ultimate origin, likely a substrate language such as Pre-Greek.
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract).