mouth breather

noun

"mouth-breather" is a 13-letter English headword indexed on PlainSpell.

The verdict

“mouth breather” is uncommon English (outside the top frequency list), classed as a noun. The kind of spelling people second-guess.

Unranked
below top-frequency English
14
letters

According to Wiktionary data (CC BY-SA, analyzed September 3, 2026) - A person who routinely inhales and exhales through the mouth, instead of through the nose.

Corpus desk

Index EN-mouth-breather · mouth breather · English

mouth breather · unranked · 0 variants · 0 confusables

  • FREQ-UNRANKED Unranked
  • LEN-MEGA 14 letters
  • VOW-5 5 vowels
  • CONFUS-0 No pairs
  • VAR-0 0 variants
  • BOOK-THIN "M" thin
  • PHOTO-UNK Peer pending

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.

Key facts for mouth breather
PropertyValue
Headwordmouth breather
LanguageEnglish
Part of speechNoun
Letters14
Misspellings tracked0
Confusable pairs0
SourceWiktionary (kaikki.org)

Long-tail rank of “mouth breather” in English

mouth breatherfalls 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

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

No generated misspelling entries exist for mouth breather in our index, since its letter sequence doesn't invite the usual edit-distance slips. It is not paired with a close-neighbour confusable in our dataset, since no other headword is close enough in sound or shape to pair with it.

No explicit etymology string is stored for this entry, so any spelling logic here comes from how the word's sounds map to letters, not a documented origin story. The correct English form is mouth breather, spelled M-O-U-T-H- -B-R-E-A-T-H-E-R.

Definition

  1. 1
    A person who routinely inhales and exhales through the mouth, instead of through the nose.
  2. 2
    A person who is boorish, stupid, or otherwise unattractive.

Recorded use

Wiktionary examples

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

  1. Respirations cannot be recorded by this method, if the subject is a mouth breather (as no air flows by the thermistor in the nose).
  2. She's a philosophy major from Brown, now working retail at Niagara Falls, living in a trailer and working for a "mouth breather" of a boss.

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 "mouth breather"?
"mouth breather" is spelled M-O-U-T-H- -B-R-E-A-T-H-E-R.
What does "mouth breather" mean?
As a noun, "mouth breather" means: A person who routinely inhales and exhales through the mouth, instead of through the nose.
What language does "mouth breather" come from?
"mouth breather" is a English word. PlainSpell's reference spans five languages -- English, Spanish, Portuguese, French, and German -- with definitions, pronunciations, and spelling data for each.
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.

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

Source: FrequencyWords open word-frequency list