formaldehyde

/fɔː(ɹ)ˈmældɪhaɪd/

//fɔː(ɹ)ˈmældɪhaɪd// noun

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

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

The verdict

“formaldehyde” has 19 generated spelling variants in the English index at frequency #30,049. The variants make it a useful spelling check.

#30,049
frequency rank, English
18,613
“F” headwords
19
tracked misspellings

According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - The simplest aldehyde, HCHO, a colourless gas that has many industrial applications; it dissolves in water to give formol (10%) and formalin.

Corpus desk

Index EN-formaldehyde · formaldehyde · English

formaldehyde · rank #30,049 · 19 variants · 0 confusables

  • FREQ-MID #30,049
  • LEN-MEGA 12 letters
  • VOW-5 5 vowels
  • CONFUS-0 No pairs
  • VAR-HIGH 19 variants
  • BOOK-DENSE 18,613
  • PHOTO-FINISH firmer

Nearest frequency peer: firmer (-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.

Frequency neighbourhood for “formaldehyde”

Lower corpus rank = more everyday usage (inverted bar length for readability)

corpus weight

What this shows Bars show where “formaldehyde” sits against the nearest ranked English headwords in the FrequencyWords band, not a reprint of letter-browse containment.

Source FrequencyWords open word-frequency list As of May 6, 2026
Key facts for formaldehyde
PropertyValue
Headwordformaldehyde
LanguageEnglish
Part of speechNoun
IPA/fɔː(ɹ)ˈmældɪhaɪd/
Letters12
Frequency rank#30,049
Misspellings tracked19
Confusable pairs0
SourceWiktionary (kaikki.org)

Where “formaldehyde” sits in English frequency

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

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

Scale is logarithmic (each tick is 10× rarer). Source: FrequencyWords open word-frequency list.

A misspelling magnet

The generator records 19 spelling variants around formaldehyde (IPA /fɔː(ɹ)ˈmældɪhaɪd/), anoun. Corpus frequency is #30,049 among 18,613 “F” headwords. Dominant gloss: "The simplest aldehyde, HCHO, a colourless gas that has many industrial applications; it dissolves in water to give formol (10%) and formalin.".

Our generated misspelling index lists 19 likely wrong-spelling variants for formaldehyde, with forms such as "fformaldehyde", "fomraldehyde", and "foramldehyde". 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 is not paired with a close-neighbour confusable in our dataset, which tends to mean the word is visually distinctive enough to stand on its own.

Etymologically, the entry records: From form(yl) + aldehyde. The correct English form is formaldehyde, spelled F-O-R-M-A-L-D-E-H-Y-D-E.

Definition

  1. 1
    The simplest aldehyde, HCHO, a colourless gas that has many industrial applications; it dissolves in water to give formol (10%) and formalin.

Etymology

From form(yl) + aldehyde.

Synonyms

E240methanal

This word in other languages

formaldehído(Español)formaldéhyde(Français)Formaldehyd(Deutsch)

Common misspellings

Also misspelled as:

  • fformaldehyde
  • fomraldehyde
  • foramldehyde
  • formadlehyde
  • formalddehyde
  • formaldehdye
  • formaldehhyde
  • formaldehydde
  • formaldehyed
  • formaldehyyde
  • formaldeyhde
  • formaldheyde
  • formaledhyde
  • formalldehyde
  • formladehyde
  • formmaldehyde
  • forrmaldehyde
  • fromaldehyde
  • ofrmaldehyde

Misspelling Pattern Breakdown

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

fformaldehyde1fomraldehyde2foramldehyde2formadlehyde2formalddehyde1formaldehdye2formaldehhyde1formaldehydde1
Edit distance from "formaldehyde"

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.

PlainSpell is rendered directly from structured Wiktionary extracts and open word-frequency lists, no number is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of May 6, 2026. Primary sources: Wiktionary (via kaikki.org) and FrequencyWords.

Frequently Asked Questions

How do you spell "formaldehyde"?
"formaldehyde" is spelled F-O-R-M-A-L-D-E-H-Y-D-E. The IPA pronunciation is /fɔː(ɹ)ˈmældɪhaɪd/.
What does "formaldehyde" mean?
As a noun, "formaldehyde" means: The simplest aldehyde, HCHO, a colourless gas that has many industrial applications; it dissolves in water to give formol (10%) and formalin.
What are common misspellings of "formaldehyde"?
Common misspellings include "fformaldehyde", "fomraldehyde", "foramldehyde", "formadlehyde", "formalddehyde". The correct spelling is "formaldehyde".
How do you pronounce "formaldehyde"?
The IPA (International Phonetic Alphabet) transcription for "formaldehyde" is /fɔː(ɹ)ˈmældɪhaɪd/. 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 "formaldehyde"?
From form(yl) + aldehyde. 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 "formaldehyde", not the corpus desk frequency band.

Same letter count

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

impressively#30,092inexperience#30,094intoxicating#30,102constabulary#29,978

Similar misspelling depth

Headwords with a similar count of attested misspellings (19 here; floor ≥5).

paraphernalia19 variantspolyethylene19 variantsrecognisable19 variantsthoroughbred19 variants
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.

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

Source: FrequencyWords open word-frequency list