long in the tooth

adj

"long-in-the-tooth" is a 14-letter English headword indexed on PlainSpell.

The verdict

“long in the tooth” is uncommon English (outside the top frequency list), classed as an adjective. The kind of spelling people second-guess.

Unranked
below top-frequency English
17
letters

According to Wiktionary data (CC BY-SA, analyzed September 3, 2026) - Old; aged.

Corpus desk

Index EN-long-in-the-tooth · long in the tooth · English

long in the tooth · unranked · 0 variants · 0 confusables

  • FREQ-UNRANKED Unranked
  • LEN-MEGA 17 letters
  • VOW-5 5 vowels
  • CONFUS-0 No pairs
  • VAR-0 0 variants
  • BOOK-THIN "L" 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 long in the tooth
PropertyValue
Headwordlong in the tooth
LanguageEnglish
Part of speechAdjective
Letters17
Misspellings tracked0
Confusable pairs0
SourceWiktionary (kaikki.org)

Long-tail rank of “long in the tooth” in English

long in the toothfalls 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

long in the tooth is uncommon English outside the top frequency list, classed as anadjective. Rarity is why readers land here mid-draft. Gloss: "Old; aged.".

Zero misspellings are on record for long in the tooth in our index, and the word's spelling is regular enough that our generator found nothing worth flagging. No close-neighbour confusable shows up for this headword in our dataset, since no other headword is close enough in sound or shape to pair with it.

Etymologically, the entry records: Possibly from the practice of examining the length of horses’ teeth when estimating their ages: an old horse has long, rectangular incisors, and their occlusion angle is steep. Compare don't look a gift horse in the mouth. The correct English form is long in the tooth, spelled L-O-N-G- -I-N- -T-H-E- -T-O-O-T-H.

Definition

  1. 1
    Old; aged.

Recorded use

Wiktionary examples

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

  1. His cousin was now of more than middle age. . . . She was lean, and yellow, and long in the tooth.
  2. So as Microsoft began its 30th year last month, investors wondered whether it's a little long in the tooth.

Etymology

Possibly from the practice of examining the length of horses’ teeth when estimating their ages: an old horse has long, rectangular incisors, and their occlusion angle is steep. Compare don't look a gift horse in the mouth.

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 "long in the tooth"?
"long in the tooth" is spelled L-O-N-G- -I-N- -T-H-E- -T-O-O-T-H.
What does "long in the tooth" mean?
As an adjective, "long in the tooth" means: Old; aged.
What is the origin of the word "long in the tooth"?
Possibly from the practice of examining the length of horses’ teeth when estimating their ages: an old horse has long, rectangular incisors, and their occlusion angle is steep. Compare don't look a gift horse in the mouth. 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