simultaneous

/ˌsɪm.əlˈteɪ̯.ni.əs/

//ˌsɪm.əlˈteɪ̯.ni.əs// adj

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

"simultaneous" is a 12-letter English headword indexed on PlainSpell.

The verdict

“simultaneous” has 17 generated spelling variants in the English index at frequency #14,414. The variants make it a useful spelling check.

#14,414
frequency rank, English
6,566
“S” headwords
17
tracked misspellings
1
confusable pair

According to Wiktionary data (CC BY-SA, analyzed September 3, 2026) - Happening at the same moment.

Corpus desk

Index EN-simultaneous · simultaneous · English

simultaneous · rank #14,414 · 17 variants · 1 confusable

  • FREQ-MID #14,414
  • LEN-MEGA 12 letters
  • VOW-6 6 vowels
  • CONFUS-LOW 1 pairs
  • VAR-HIGH 17 variants
  • BOOK-DENSE 6,566
  • PHOTO-FINISH severed

Nearest frequency peer: severed (-2 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 “simultaneous”

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

corpus weight

What this shows “simultaneous” 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).

simultaneous vs simultaneously
86% similar

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

Key facts for simultaneous
PropertyValue
Headwordsimultaneous
LanguageEnglish
Part of speechAdjective
IPA/ˌsɪm.əlˈteɪ̯.ni.əs/
Letters12
Frequency rank#14,414
Misspellings tracked17
Confusable pairs1
SourceWiktionary (kaikki.org)

Frequency seat of misspelling magnet “simultaneous”

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

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

Scale is logarithmic (each tick is 10× rarer). Same rarity band neighbours include “severed” (#14,412), “snatch” (#14,416), “Serbian” (#14,411). Among 6,566 “S” headwords, “simultaneous” is #14,414. Source: FrequencyWords open word-frequency list.

A misspelling magnet

The generator records 17 spelling variants around simultaneous (IPA /ˌsɪm.əlˈteɪ̯.ni.əs/), anadjective. Corpus frequency is #14,414 among 6,566 “S” headwords. Wiktionary lists 2 senses, so context still picks the gloss.

Our generated misspelling index lists 17 likely wrong-spelling variants for simultaneous, with forms such as "ismultaneous", "simlutaneous", and "simmultaneous". Each variant is a distinct typo pattern an edit-distance generator flags, typically a doubled-consonant error, a silent-letter drop, or a vowel substitution. It also participates in 1 confusable-pair relationship, "simultaneously", where similar look or sound leads writers to substitute one word for another in context.

Etymologically, the entry records: From Medieval Latin simultaneus, from simultim (“at the same time, extended”), from Latin simul (“together, at the same time”); compare similar. The correct English form is simultaneous, spelled S-I-M-U-L-T-A-N-E-O-U-S.

Definition

  1. 1
    Happening at the same moment.
  2. 2
    To be solved for the same values of variables.

Recorded use

Wiktionary example

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

  1. As with the Lejeuneaceae, this pattern of massive speciation appears to be correlated with the Cretaceous explosion of the angiosperms and the simultaneous creation of a host of new microenvironments, differing in humidity, light intensity, texture, etc.

Etymology

From Medieval Latin simultaneus, from simultim (“at the same time, extended”), from Latin simul (“together, at the same time”); compare similar.

Synonyms

coincidentcoincidentalconcomitantconcurrenthomochronousisochronoussimultaneoussynchronalsynchronicalsynchronous

Antonyms

sequentialasynchronousmetachronousantisynchronousasynchronicheterochronouspolychronicuncoincidentalunconcurrentnoncoincidentnoncoincidentalnonconcurrentnonisochronousnonsimultaneousnonsynchronous

This word in other languages

simultáneo(Español)simultané(Français)gleichzeitig(Deutsch)simultâneo(Português)

Common misspellings

Also misspelled as:

  • ismultaneous
  • simlutaneous
  • simmultaneous
  • simulatneous
  • simulltaneous
  • simultaenous
  • simultaneosu
  • simultaneouss
  • simultaneuos
  • simultanneous
  • simultanoeus
  • simultnaeous
  • simulttaneous
  • simutlaneous
  • siumltaneous
  • smiultaneous
  • ssimultaneous

Misspelling Pattern Breakdown

How far each generated variant is from the correct spelling of simultaneous - measured in single-character edits (insert, delete, or substitute a letter). Larger bars are easier to catch; one-edit slips are the sneakiest.

ismultaneous2simlutaneous2simmultaneous1simulatneous2simulltaneous1simultaenous2simultaneosu2simultaneouss1
Edit distance from "simultaneous"

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 "simultaneous"?
"simultaneous" is spelled S-I-M-U-L-T-A-N-E-O-U-S. The IPA pronunciation is /ˌsɪm.əlˈteɪ̯.ni.əs/.
What does "simultaneous" mean?
As an adjective, "simultaneous" means: Happening at the same moment.
What words are commonly confused with "simultaneous"?
"simultaneous" is commonly confused with "simultaneously". These words look or sound similar but have different meanings. PlainSpell provides detailed comparisons for each pair.
How do you pronounce "simultaneous"?
The IPA (International Phonetic Alphabet) transcription for "simultaneous" is /ˌsɪm.əlˈteɪ̯.ni.əs/. 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 "simultaneous"?
From Medieval Latin simultaneus, from simultim (“at the same time, extended”), from Latin simul (“together, at the same time”); compare similar. 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 "simultaneous", not the corpus desk frequency band.

Same letter count

Frequency-ranked English headwords with 12 letters (nearest by frequency rank).

condemnation#14,497disconnected#14,514encyclopedia#14,520communicated#14,298

Similar misspelling depth

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

sentimental17 variantsreformation17 variantsmagistrates17 variantsinterfering17 variants

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

Source: FrequencyWords open word-frequency list