thick as thieves
"thick-as-thieves" is a 14-letter English headword indexed on PlainSpell.
The verdict
“thick as thieves” is uncommon English (outside the top frequency list), classed as an adjective. The kind of spelling people second-guess.
- Unranked
- below top-frequency English
- 16
- letters
According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - Intimate, close-knit, tight.
| Property | Value |
|---|---|
| Headword | thick as thieves |
| Language | English |
| Part of speech | Adjective |
| Letters | 16 |
| Misspellings tracked | 0 |
| Confusable pairs | 0 |
| Source | Wiktionary (kaikki.org) |
Where “thick as thieves” sits in English frequency
Rare enough to double-check
thick as thieves is uncommon English outside the top frequency list, classed as anadjective. Rarity is why readers land here mid-draft. Gloss: "Intimate, close-knit, tight.".
thick as thieves has no tracked misspelling variants, typically a sign the spelling maps closely to how the word sounds. We don't track a confusable pairing for this entry, since nothing in our dataset looks or sounds close enough to cause mix-ups.
Etymologically, the entry records: From thick (“friendly, intimate”), first attested in 1827 as "thick as two thieves". The correct English form is thick as thieves, spelled T-H-I-C-K- -A-S- -T-H-I-E-V-E-S.
Definition
- 1Intimate, close-knit, tight.
Etymology
From thick (“friendly, intimate”), first attested in 1827 as "thick as two thieves".
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
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Using “thick as thieves”
The practical upshot for anyone who landed here from a spell-check.
- The one correct English spelling is T-H-I-C-K- -A-S- -T-H-I-E-V-E-S - 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.