infirmity

/ɪnˈfɜːmɪti/

//ɪnˈfɜːmɪti// noun

By · According to Wiktionary data (CC BY-SA) ·

"infirmity" is a 9-letter English headword indexed on PlainSpell.

The verdict

“infirmity” is an uncommon English word, ranked #65,208 in English word frequency and used as a noun.

#65,208
frequency rank, English
9
letters

According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - Feebleness, frailty or ailment, especially due to old age.

Key facts for infirmity
PropertyValue
Headwordinfirmity
LanguageEnglish
Part of speechNoun
IPA/ɪnˈfɜːmɪti/
Letters9
Frequency rank#65,208
Misspellings tracked0
Confusable pairs0
SourceWiktionary (kaikki.org)

Where “infirmity” sits in English frequency

Every-word frequency runs from the handful of words we use constantly (left) to the long tail used once in a blue moon (right). infirmity lands here:

#1#100#1K#10K#100K
← used constantlyrarely used →

Scale is logarithmic (each tick is 10× rarer). Source: FrequencyWords open word-frequency list.

Spelling & Dictionary Insight

The English entry for infirmity is 9 letters long, classified as a noun, and transcribed in the International Phonetic Alphabet as /ɪnˈfɜːmɪti/. Corpus data places it at rank #65,208 in overall English word frequency, marking it as uncommon enough that many writers pause before typing it. Wiktionary records 2 distinct senses for this headword, so context determines which meaning a reader should apply.

Our edit-distance generator produced no likely misspellings for infirmity, 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, a sign it's visually distinctive enough not to be mixed up with another word.

Etymologically, the entry records: From infirm + -ity. The correct English form is infirmity, spelled I-N-F-I-R-M-I-T-Y.

Definition

  1. 1
    Feebleness, frailty or ailment, especially due to old age.
  2. 2
    A moral weakness or defect.

Etymology

From infirm + -ity.

This word in other languages

enfermedad(Español)infirmité(Français)Gebrechlichkeit(Deutsch)

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

How do you spell "infirmity"?
"infirmity" is spelled I-N-F-I-R-M-I-T-Y. The IPA pronunciation is /ɪnˈfɜːmɪti/.
What does "infirmity" mean?
As a noun, "infirmity" means: Feebleness, frailty or ailment, especially due to old age.
How do you pronounce "infirmity"?
The IPA (International Phonetic Alphabet) transcription for "infirmity" is /ɪnˈfɜːmɪti/. Click the speaker icon on the pronunciation badge above to hear it spoken aloud where audio is available.
What is the origin of the word "infirmity"?
From infirm + -ity. 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.

Using “infirmity”

The practical upshot for anyone who landed here from a spell-check.

  • The one correct English spelling is I-N-F-I-R-M-I-T-Y - every other letter order is a misspelling in standard orthography.
  • Say it as /ɪnˈfɜːmɪti/ (IPA); tap the speaker on the pronunciation badge to hear it where audio exists.
  • 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.

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

Source: FrequencyWords open word-frequency list FrequencyWords open word-frequency list