infectious

/ɪnˈfɛk.ʃəs/

//ɪnˈfɛk.ʃəs// adj

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

"infectious" is a 10-letter English headword indexed on PlainSpell.

The verdict

“infectious” has 14 generated spelling variants in the English index at frequency #9,481. The variants make it a useful spelling check.

#9,481
frequency rank, English
2,140
“I” headwords
14
tracked misspellings
2
confusable pairs

According to Wiktionary data (CC BY-SA, analyzed September 3, 2026) - Caused by an agent that enters the host's body (such as a bacterium, virus, parasite, or prion); often, also, transmitted among hosts via any of various routes (for example, contact, droplet-borne,...

Corpus desk

Index EN-infectious · infectious · English

infectious · rank #9,481 · 14 variants · 2 confusables

  • FREQ-COMMON #9,481
  • LEN-MEGA 10 letters
  • VOW-5 5 vowels
  • CONFUS-LOW 2 pairs
  • VAR-HIGH 14 variants
  • BOOK-MID 2,140
  • PHOTO-FINISH honorable

Nearest frequency peer: honorable (-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 “infectious”

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

corpus weight

What this shows “infectious” 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).

infectious vs injections
80% similar
infectious vs infection
80% similar

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

Key facts for infectious
PropertyValue
Headwordinfectious
LanguageEnglish
Part of speechAdjective
IPA/ɪnˈfɛk.ʃəs/
Letters10
Frequency rank#9,481
Misspellings tracked14
Confusable pairs2
SourceWiktionary (kaikki.org)

Frequency seat of misspelling magnet “infectious”

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).infectiouslands here:

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

Scale is logarithmic (each tick is 10× rarer). Same rarity band neighbours include “honorable” (#9,480), “inferior” (#9,482), “homemade” (#9,479). Among 2,140 “I” headwords, “infectious” is #9,481. Source: FrequencyWords open word-frequency list.

A misspelling magnet

The generator records 14 spelling variants around infectious (IPA /ɪnˈfɛk.ʃəs/), anadjective. Corpus frequency is #9,481 among 2,140 “I” headwords. Wiktionary lists 4 senses, so context still picks the gloss.

Our generated misspelling index lists 14 likely wrong-spelling variants for infectious, with forms such as "ifnectious", "inefctious", and "infcetious". 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 2 confusable-pair relationships, "injections", "infection", since the words sound or look close enough that writers reach for the wrong one mid-sentence.

Etymologically, the entry records: Borrowed from New Latin īnfectiōsus. By surface analysis, infect + -ious. The correct English form is infectious, spelled I-N-F-E-C-T-I-O-U-S.

Definition

  1. 1
    Caused by an agent that enters the host's body (such as a bacterium, virus, parasite, or prion); often, also, transmitted among hosts via any of various routes (for example, contact, droplet-borne, airborne, waterborne, foodborne, fomite-borne, or bloodborne).
  2. 2
    Able to infect others; capable of transmitting pathogens.
  3. 3
    Spreading quickly from one person to another.
  4. 4
    Memorable and invoking excitement or interest.

Recorded use

Wiktionary examples

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

  1. Cancer is usually not infectious.
  2. More infectious diseases like the flu are usually less potent.

Etymology

Borrowed from New Latin īnfectiōsus. By surface analysis, infect + -ious.

Antonyms

non-infectiousnoninfectious

This word in other languages

infeccioso(Español)infectieux(Français)infektiös(Deutsch)infeccioso(Português)

Common misspellings

Also misspelled as:

  • ifnectious
  • inefctious
  • infcetious
  • infecctious
  • infecitous
  • infectiosu
  • infectiouss
  • infectiuos
  • infectoius
  • infecttious
  • infetcious
  • inffectious
  • innfectious
  • nifectious

Misspelling Pattern Breakdown

How far each generated variant is from the correct spelling of infectious - 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.

ifnectious2inefctious2infcetious2infecctious1infecitous2infectiosu2infectiouss1infectiuos2
Edit distance from "infectious"

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 "infectious"?
"infectious" is spelled I-N-F-E-C-T-I-O-U-S. The IPA pronunciation is /ɪnˈfɛk.ʃəs/.
What does "infectious" mean?
As an adjective, "infectious" means: Caused by an agent that enters the host's body (such as a bacterium, virus, parasite, or prion); often, also, transmitted among hosts via any of various routes (for example, contact, droplet-borne,...
What words are commonly confused with "infectious"?
"infectious" is commonly confused with "injections", "infection". These words look or sound similar but have different meanings. PlainSpell provides detailed comparisons for each pair.
How do you pronounce "infectious"?
The IPA (International Phonetic Alphabet) transcription for "infectious" is /ɪnˈfɛk.ʃəs/. 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 "infectious"?
Borrowed from New Latin īnfectiōsus. By surface analysis, infect + -ious. 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 "infectious", not the corpus desk frequency band.

Same letter count

Frequency-ranked English headwords with 10 letters (nearest by frequency rank).

competitor#9,453privileged#9,512protestant#9,515algorithms#9,433

Similar misspelling depth

Headwords with a similar count of attested misspellings (14 here; floor ≥5).

honorable14 variantsinterpret14 variantsenjoyment14 variantselephants14 variants

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

Source: FrequencyWords open word-frequency list