glaucus

/ˈɡlɔːkəs/

//ˈɡlɔːkəs// noun

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

The verdict

“glaucus” is uncommon English (frequency #92,648 among 2,313 “G” headwords), classed as a noun. The kind of spelling people second-guess.

#92,648
frequency rank, English
2,313
“G” headwords

According to Wiktionary data (CC BY-SA, analyzed September 3, 2026) - Any member of the genus Glaucus of nudibranchiate mollusks, found in the warmer latitudes, swimming in the open sea, strikingly colored with blue and silvery white.

Corpus desk

Index EN-glaucus · glaucus · English

glaucus · rank #92,648 · 0 variants · 0 confusables

  • FREQ-RARE #92,648
  • LEN-LONG 7 letters
  • VOW-3 3 vowels
  • CONFUS-0 No pairs
  • VAR-0 0 variants
  • BOOK-MID 2,313
  • PHOTO-FINISH Gladwin

Nearest frequency peer: Gladwin (-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.

Long-tail ranks near “glaucus”

Sparse band: bars invert rank so rarer forms read shorter

corpus weight

What this shows Long-tail view: where “glaucus” sits against similarly uncommon English ranks.

Source FrequencyWords open word-frequency list As of September 3, 2026
Key facts for glaucus
PropertyValue
Headwordglaucus
LanguageEnglish
Part of speechNoun
IPA/ˈɡlɔːkəs/
Letters7
Frequency rank#92,648
Misspellings tracked0
Confusable pairs0
SourceWiktionary (kaikki.org)

Long-tail rank of “glaucus” in English

Every-word frequency runs from the handful of words we use constantly (left) to the long tail used once in a blue moon (right).glaucusfalls in this rarity band:

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

Scale is logarithmic (each tick is 10× rarer). Rare peers in the same band: “Gladwin” (#92,647), “Ghassan” (#92,641), “genitourinary” (#92,638). Among 2,313 “G” headwords, “glaucus” is #92,648. Source: FrequencyWords open word-frequency list.

Rare enough to double-check

glaucus is uncommon English at frequency #92,648 among 2,313 “G” headwords, classed as anoun, transcribed /ˈɡlɔːkəs/. Rarity is why readers land here mid-draft. 2 senses are on record.

glaucus doesn't appear in our generated misspelling index, which points to an orthography that plays by predictable English rules. No close-neighbour confusable shows up for this headword in our dataset, since nothing in our dataset looks or sounds close enough to cause mix-ups.

Etymologically, the entry records: Borrowed from translingual Glaucus, from Latin glaucus, from Ancient Greek γλαῦκος (glaûkos, “blue-grey fish”), from γλαυκός (glaukós, “blue-green, blue-grey”). The correct English form is glaucus, spelled G-L-A-U-C-U-S.

Definition

  1. 1
    Any member of the genus Glaucus of nudibranchiate mollusks, found in the warmer latitudes, swimming in the open sea, strikingly colored with blue and silvery white.
  2. 2
    A desert lime (Citrus glauca), a thorny shrub species endemic to semi-arid regions of Australia.

Recorded use

Wiktionary example

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

  1. This pass is extremely abrupt, and is covered with glaucus, the low scrub I have noticed as common to the sand-stone formation.

Etymology

Borrowed from translingual Glaucus, from Latin glaucus, from Ancient Greek γλαῦκος (glaûkos, “blue-grey fish”), from γλαυκός (glaukós, “blue-green, blue-grey”).

Synonyms

sea swallowblue angelblue glaucusblue dragonblue sea slugblue ocean slug

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 "glaucus"?
"glaucus" is spelled G-L-A-U-C-U-S. The IPA pronunciation is /ˈɡlɔːkəs/.
What does "glaucus" mean?
As a noun, "glaucus" means: Any member of the genus Glaucus of nudibranchiate mollusks, found in the warmer latitudes, swimming in the open sea, strikingly colored with blue and silvery white.
How do you pronounce "glaucus"?
The IPA (International Phonetic Alphabet) transcription for "glaucus" is /ˈɡlɔːkəs/. 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 "glaucus"?
Borrowed from translingual Glaucus, from Latin glaucus, from Ancient Greek γλαῦκος (glaûkos, “blue-grey fish”), from γλαυκός (glaukós, “blue-green, blue-grey”). 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 "glaucus", not the corpus desk frequency band.

Same letter count

Frequency-ranked English headwords with 7 letters (nearest by frequency rank).

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

Source: FrequencyWords open word-frequency list