deep blue

adj

"deep-blue" is a 8-letter English headword indexed on PlainSpell.

The verdict

“deep blue” is uncommon English (outside the top frequency list), classed as an adjective. The kind of spelling people second-guess.

Unranked
below top-frequency English
9
letters

According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - An intense, relatively dark blue.

Key facts for deep blue
PropertyValue
Headworddeep blue
LanguageEnglish
Part of speechAdjective
Letters9
Misspellings tracked0
Confusable pairs0
SourceWiktionary (kaikki.org)

Where “deep blue” sits in English frequency

deep blue 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.

Rare enough to double-check

deep blue is uncommon English outside the top frequency list, classed as anadjective. Rarity is why readers land here mid-draft. 2 senses are on record.

No generated misspelling entries exist for deep blue in our index, suggesting the orthography follows predictable English patterns. We don't track a confusable pairing for this entry, a sign it's visually distinctive enough not to be mixed up with another word.

Etymologically, the entry records: From Middle English depe blew, equivalent to deep + blue. The correct English form is deep blue, spelled D-E-E-P- -B-L-U-E.

Definition

  1. 1
    An intense, relatively dark blue.
  2. 2
    An extremely Democratic-leaning area.

Etymology

From Middle English depe blew, equivalent to deep + blue.

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 "deep blue"?
"deep blue" is spelled D-E-E-P- -B-L-U-E.
What does "deep blue" mean?
As an adjective, "deep blue" means: An intense, relatively dark blue.
What is the origin of the word "deep blue"?
From Middle English depe blew, equivalent to deep + blue. 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 “deep blue”

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

  • The one correct English spelling is D-E-E-P- -B-L-U-E - 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