deep down

adv

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

The verdict

“deep down” is outside the top-ranked English vocabulary, used as an adverb - the kind of word writers most often double-check.

Unranked
below top-frequency English
9
letters

According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - Fundamentally; in essence; in reality

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

Where “deep down” sits in English frequency

deep down 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.

Spelling & Dictionary Insight

The English entry for deep down is 9 letters long, classified as an adverb. It sits outside the most-frequent rank tiers, which is often why uncommon words generate more spelling variants per reader. The dominant gloss from Wiktionary reads: "Fundamentally; in essence; in reality".

We couldn't generate a plausible misspelling set for deep down, and the word's spelling is regular enough that our generator found nothing worth flagging. No confusable counterpart is on file for this word, which tends to mean the word is visually distinctive enough to stand on its own.

No borrowing history is documented for this entry, so its spelling is best read as a straightforward mapping from sound to letter. The correct English form is deep down, spelled D-E-E-P- -D-O-W-N.

Definition

  1. 1
    Fundamentally; in essence; in reality

Synonyms

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). See the methodology for how each field is sourced and updated.

Frequently Asked Questions

How do you spell "deep down"?
"deep down" is spelled D-E-E-P- -D-O-W-N.
What does "deep down" mean?
As an adverb, "deep down" means: Fundamentally; in essence; in reality
What language does "deep down" come from?
"deep down" is a English word. You can look up definitions, pronunciations, and spelling data for this and other words across English, Spanish, Portuguese, French, and German on PlainSpell.
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 down”

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

  • The one correct English spelling is D-E-E-P- -D-O-W-N - 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