instability
"instability" is a 11-letter English headword indexed on PlainSpell.
The verdict
“instability” is a moderately-common English word, ranked #11,051 in English word frequency and used as a noun.
- #11,051
- frequency rank, English
- 11
- letters
- 17
- tracked misspellings
- 1
- confusable pair
According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - The quality of being unstable.
Visual similarity to commonly confused words
How many letter changes separate each confused pair (Levenshtein distance, normalized).
Source: PlainSpell confusable corpus (Wiktionary, CC BY-SA).
| Property | Value |
|---|---|
| Headword | instability |
| Language | English |
| Part of speech | Noun |
| Letters | 11 |
| Frequency rank | #11,051 |
| Misspellings tracked | 17 |
| Confusable pairs | 1 |
| Source | Wiktionary (kaikki.org) |
Where “instability” sits in English frequency
Spelling & Dictionary Insight
The English entry for instability is 11 letters long, classified as a noun. Corpus data places it at rank #11,051 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 generated misspelling index lists 17 likely wrong-spelling variants for instability, with forms such as "innstability", "insatbility", and "insstability". Each of these forms differs from the correct spelling by one small edit: a doubled letter, a dropped silent letter, or a substituted vowel. It also participates in 1 confusable-pair relationship, "inability", where similar look or sound leads writers to substitute one word for another in context.
Etymologically, the entry records: From Middle French instabilité, from Latin instabilitas. Morphologically in- + stability. The correct English form is instability, spelled I-N-S-T-A-B-I-L-I-T-Y.
Definition
- 1The quality of being unstable.
- 2A state that is not in equilibrium, or in which a small change has a large irreversible effect.
Etymology
From Middle French instabilité, from Latin instabilitas. Morphologically in- + stability.
This word in other languages
Common misspellings
Also misspelled as: innstability,insatbility,insstability,instabbility,instabiilty,instabilitty,instabilityy,instabiliyt,instabillity,instabiltiy,instabliity,instaiblity,instbaility,insttability,intsability,isntability,nistability
Misspelling Pattern Breakdown
How far each generated variant is from the correct spelling of instability - measured in single-character edits (insert, delete, or substitute a letter). Larger bars are easier to catch; one-edit slips are the sneakiest.
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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Using “instability”
The practical upshot for anyone who landed here from a spell-check.
- The one correct English spelling is I-N-S-T-A-B-I-L-I-T-Y - every other letter order is a misspelling in standard orthography.
- Don't mix it up with “inability” - see the side-by-side comparison. instability vs inability
- 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.