glass jaw

noun

"glass-jaw" is a 8-letter English headword indexed on PlainSpell.

The verdict

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

Unranked
below top-frequency English
9
letters

According to Wiktionary data (CC BY-SA, analyzed September 3, 2026) - A fighting vulnerability where one is easily knocked out via a single hard blow to the chin or jaw (due to lack of conditioning, insufficient training, or damage from past cerebral concussions).

Corpus desk

Index EN-glass-jaw · glass jaw · English

glass jaw · unranked · 0 variants · 0 confusables

  • FREQ-UNRANKED Unranked
  • LEN-LONG 9 letters
  • VOW-2 2 vowels
  • CONFUS-0 No pairs
  • VAR-0 0 variants
  • BOOK-THIN "G" 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 glass jaw
PropertyValue
Headwordglass jaw
LanguageEnglish
Part of speechNoun
Letters9
Misspellings tracked0
Confusable pairs0
SourceWiktionary (kaikki.org)

Long-tail rank of “glass jaw” in English

glass jawranks outside the top 100,000 English headwords, in the long tail of specialist, archaic, or seldom-used vocabulary, exactly the territory where a reader stops mid-sentence to double-check spelling.

Beyond rank #100,000. Source: FrequencyWords open word-frequency list.

Rare enough to double-check

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

glass jaw doesn't appear in our generated misspelling index, and the word's spelling is regular enough that our generator found nothing worth flagging. This headword has no recorded confusable partner, suggesting its spelling stands apart enough that readers rarely confuse it with something else.

Etymologically, the entry records: An allusion to glass being easily breakable. The correct English form is glass jaw, spelled G-L-A-S-S- -J-A-W.

Definition

  1. 1
    A fighting vulnerability where one is easily knocked out via a single hard blow to the chin or jaw (due to lack of conditioning, insufficient training, or damage from past cerebral concussions).
  2. 2
    A vulnerability of that sort; a weak spot.

Recorded use

Wiktionary examples

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

  1. "How was I to know that big ape had a glass jaw?"
  2. Early in Ali's career, experts believed he had what's called a glass jaw—that he would fall after the first big punch. He was now proving that he could take a punch, but each punch chipped away at his health.

Etymology

An allusion to glass being easily breakable.

Synonyms

glass chinbad chin

Antonyms

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 "glass jaw"?
"glass jaw" is spelled G-L-A-S-S- -J-A-W.
What does "glass jaw" mean?
As a noun, "glass jaw" means: A fighting vulnerability where one is easily knocked out via a single hard blow to the chin or jaw (due to lack of conditioning, insufficient training, or damage from past cerebral concussions).
What is the origin of the word "glass jaw"?
An allusion to glass being easily breakable. 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.

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

Source: FrequencyWords open word-frequency list