soundproof
"soundproof" is a 10-letter English headword indexed on PlainSpell.
The verdict
“soundproof” is uncommon English (frequency #57,725 among 6,566 “S” headwords), classed as an adjective. The kind of spelling people second-guess.
- #57,725
- frequency rank, English
- 6,566
- “S” headwords
According to Wiktionary data (CC BY-SA, analyzed September 3, 2026) - Not allowing sound through.
Corpus desk
Index EN-soundproof · soundproof · English
soundproof · rank #57,725 · 0 variants · 0 confusables
- FREQ-RARE #57,725
- LEN-MEGA 10 letters
- VOW-4 4 vowels
- CONFUS-0 No pairs
- VAR-0 0 variants
- BOOK-DENSE 6,566
- PHOTO-FINISH soonest
Nearest frequency peer: soonest (-2 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 “soundproof”
Sparse band: bars invert rank so rarer forms read shorter
- smokehouse
smokehouse
42,283 corpus weight
- soonest
soonest
42,278 corpus weight
- soundproof
soundproof
42,276 corpus weight
- spacewalk
spacewalk
42,274 corpus weight
- spay
spay
42,273 corpus weight
- sprig
sprig
42,271 corpus weight
What this shows Long-tail view: where “soundproof” sits against similarly uncommon English ranks.
| Property | Value |
|---|---|
| Headword | soundproof |
| Language | English |
| Part of speech | Adjective |
| Letters | 10 |
| Frequency rank | #57,725 |
| Misspellings tracked | 0 |
| Confusable pairs | 0 |
| Source | Wiktionary (kaikki.org) |
Long-tail rank of “soundproof” in English
Rare enough to double-check
soundproof is uncommon English at frequency #57,725 among 6,566 “S” headwords, classed as anadjective. Rarity is why readers land here mid-draft. Gloss: "Not allowing sound through.".
We couldn't generate a plausible misspelling set for soundproof, a straightforward case of a spelling with little room for common typos. Our confusable-pair dataset has no match for it, since no other headword is close enough in sound or shape to pair with it.
Etymologically, the entry records: From sound + -proof. The correct English form is soundproof, spelled S-O-U-N-D-P-R-O-O-F.
Definition
- 1Not allowing sound through.
Recorded use
Wiktionary examplesThese source excerpts show how soundproof appears in context. They illustrate usage; the definition above remains the entry’s reference meaning.
The contestant was placed in a soundproof booth so he could not receive help from the audience.
The electrical activity of the subject's cerebral cortex was recorded in a state of relative rest, after a 5 min adaptation of the subject to a dark soundproof chamber. The biopotentials were recorded from the electroencephaloscope screen […]
Etymology
From sound + -proof.
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); 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
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Similar English words by spelling shape
Same letter count and similar misspelling depth for "soundproof", not the corpus desk frequency band.
Same letter count
Frequency-ranked English headwords with 10 letters (nearest by frequency rank).