instability

Name: instability, English Word Data
Creator: Wiktionary
License: https://creativecommons.org/licenses/by-sa/4.0/

noun

By PlainSpell · According to Wiktionary data (CC BY-SA) · analyzed September 3, 2026

The verdict

“instability” has 17 generated spelling variants in the English index at frequency #11,051. The variants make it a useful spelling check.

#11,051
frequency rank, English: 2,140
“I” headwords: 17
tracked misspellings: 1
confusable pair

According to Wiktionary data (CC BY-SA, analyzed September 3, 2026) - The quality of being unstable.

Corpus desk

Index EN-instability · instability · English

instability · rank #11,051 · 17 variants · 1 confusable

FREQ-MID #11,051
LEN-MEGA 11 letters
VOW-5 5 vowels
CONFUS-LOW 1 pairs
VAR-HIGH 17 variants
BOOK-MID 2,140
PHOTO-FINISH insists

Nearest frequency peer: insists (-1 rank slots)

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.

indirectly

88,954
induction

88,953
infrared

88,952
insists

88,951
instability

88,950
Irene

88,947

What this shows “instability” sits among these FrequencyWords peers; misspelling depth is tracked separately in the edit-distance chart.

Visual similarity to commonly confused words

How many letter changes separate each confused pair (Levenshtein distance, normalized).

instability vs inability

82% similar

Source: PlainSpell confusable corpus (Wiktionary, CC BY-SA).

Key facts for instability
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)

Frequency seat of misspelling magnet “instability”

This scale runs from the tiny cluster of words that carry ordinary speech (left) to the long tail of words almost nobody reaches for (right).instabilitylands here:

#11,051

#1#100#1K#10K#100K

← used constantlyrarely used →

Ticks step logarithmically, so each one marks a roughly tenfold drop in how often the word turns up. Same rarity band neighbours include “insists” (#11,050), “infrared” (#11,049), “induction” (#11,048). Among 2,140 “I” headwords, “instability” is #11,051. Source: FrequencyWords open word-frequency list.

A misspelling magnet

The generator records 17 spelling variants around instability, anoun. Corpus frequency is #11,051 among 2,140 “I” headwords. Wiktionary lists 2 senses, so context still picks the gloss.

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

1
The quality of being unstable.
2
A 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

inestabilidad(Español)instabilité(Français)Instabilität(Deutsch)instabilidade(Português)

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.

Edit distance from "instability"

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 "instability"?

"instability" is spelled I-N-S-T-A-B-I-L-I-T-Y.

What does "instability" mean?

As a noun, "instability" means: The quality of being unstable.

What words are commonly confused with "instability"?

"instability" is commonly confused with "inability". These words look or sound similar but have different meanings. PlainSpell provides detailed comparisons for each pair.

What is the origin of the word "instability"?

From Middle French instabilité, from Latin instabilitas. Morphologically in- + stability. 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.

Similar English words by spelling shape

Same letter count and similar misspelling depth for "instability", not the corpus desk frequency band.

Same letter count

Frequency-ranked English headwords with 11 letters (nearest by frequency rank).

impressions#11,046 observatory#11,080 descendants#11,016 penetration#11,086

Similar misspelling depth

Headwords with a similar count of attested misspellings (17 here; floor ≥5).

voluntarily17 variants undertaking17 variants counterpart17 variants philosopher17 variants