fission

/ˈfɪʃən/

//ˈfɪʃən// noun

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

"fission" is a 7-letter English headword indexed on PlainSpell.

The verdict

“fission” has 9 generated spelling variants in the English index at frequency #25,059. The variants make it a useful spelling check.

#25,059
frequency rank, English
2,507
“F” headwords
9
tracked misspellings
4
confusable pairs

According to Wiktionary data (CC BY-SA, analyzed September 3, 2026) - The process whereby one item splits to become two.

Corpus desk

Index EN-fission · fission · English

fission · rank #25,059 · 9 variants · 4 confusables

  • FREQ-MID #25,059
  • LEN-LONG 7 letters
  • VOW-3 3 vowels
  • CONFUS-MID 4 pairs
  • VAR-MID 9 variants
  • BOOK-MID 2,507
  • PHOTO-FINISH fives

Nearest frequency peer: fives (+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.

Rank peers near misspelling magnet “fission”

Same rarity band: useful when a typo lands on a peer headword

corpus weight

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

Source FrequencyWords open word-frequency list As of September 3, 2026

Visual similarity to commonly confused words

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

fission vs fusion
71% similar
fission vs fashion
71% similar
fission vs fiction
71% similar

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

Key facts for fission
PropertyValue
Headwordfission
LanguageEnglish
Part of speechNoun
IPA/ˈfɪʃən/
Letters7
Frequency rank#25,059
Misspellings tracked9
Confusable pairs4
SourceWiktionary (kaikki.org)

Frequency seat of misspelling magnet “fission”

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

#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 “fives” (#25,060), “Fergus” (#25,057), “fleas” (#25,061). Among 2,507 “F” headwords, “fission” is #25,059. Source: FrequencyWords open word-frequency list.

A misspelling magnet

The generator records 9 spelling variants around fission (IPA /ˈfɪʃən/), anoun. Corpus frequency is #25,059 among 2,507 “F” headwords. Wiktionary lists 3 senses, so context still picks the gloss.

Our generated misspelling index lists 9 likely wrong-spelling variants for fission, with forms such as "ffission", "fision", and "fisison". Every one of these variants traces to a single-character edit -- an added or dropped letter, a swapped consonant, or a vowel swap -- the kind of slip a spell-checker is built to catch. It also participates in 4 confusable-pair relationships, "fusion", "fashion", "fiction", and more, a pairing that trips writers up because the two words share enough sound or shape to blur together.

Etymologically, the entry records: Borrowed from Latin fissiōnem, accusative singular of fissiō (“the act of breaking up”), from findō (“split, divide”). The correct English form is fission, spelled F-I-S-S-I-O-N.

Definition

  1. 1
    The process whereby one item splits to become two.
  2. 2
    nuclear fission: The process of splitting the nucleus of an atom into smaller particles.
  3. 3
    The process by which a bacterium splits to form two daughter cells.

Etymology

Borrowed from Latin fissiōnem, accusative singular of fissiō (“the act of breaking up”), from findō (“split, divide”).

This word in other languages

fisión(Español)fission(Français)Spaltung(Deutsch)fissão(Português)

Common misspellings

Also misspelled as:

  • ffission
  • fision
  • fisison
  • fissino
  • fissionn
  • fissoin
  • fistion
  • fsision
  • ifssion

Misspelling Pattern Breakdown

How far each generated variant is from the correct spelling of fission - counted as single-character edits (an insertion, a deletion, or a substituted letter). The larger the bar, the easier the typo is to spot; one-edit slips are the ones that sneak past readers.

ffission1fision1fisison2fissino2fissionn1fissoin2fistion1fsision2
Edit distance from "fission"

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 "fission"?
"fission" is spelled F-I-S-S-I-O-N. The IPA pronunciation is /ˈfɪʃən/.
What does "fission" mean?
As a noun, "fission" means: The process whereby one item splits to become two.
What words are commonly confused with "fission"?
"fission" is commonly confused with "fusion", "fashion", "fiction". These words look or sound similar but have different meanings. PlainSpell provides detailed comparisons for each pair.
How do you pronounce "fission"?
The IPA (International Phonetic Alphabet) transcription for "fission" is /ˈfɪʃən/. 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 "fission"?
Borrowed from Latin fissiōnem, accusative singular of fissiō (“the act of breaking up”), from findō (“split, divide”). 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 "fission", not the corpus desk frequency band.

Same letter count

Frequency-ranked English headwords with 7 letters (nearest by frequency rank).

fanning#25,055esquire#25,052genomic#25,070Gestapo#25,071

Similar misspelling depth

Headwords with a similar count of attested misspellings (9 here; floor ≥5).

Fergus9 variantsFarley9 variantsfrugal9 variantsglimmer9 variants

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

Source: FrequencyWords open word-frequency list