thickness

/ˈθɪknəs/

//ˈθɪknəs// noun

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

"thickness" is a 9-letter English headword indexed on PlainSpell.

The verdict

“thickness” is a moderately-common English word, ranked #10,464 in English word frequency and used as a noun.

#10,464
frequency rank, English
9
letters
13
tracked misspellings

According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - The property of being thick (in dimension).

Key facts for thickness
PropertyValue
Headwordthickness
LanguageEnglish
Part of speechNoun
IPA/ˈθɪknəs/
Letters9
Frequency rank#10,464
Misspellings tracked13
Confusable pairs0
SourceWiktionary (kaikki.org)

Where “thickness” 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). thickness lands here:

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

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

Spelling & Dictionary Insight

The English entry for thickness is 9 letters long, classified as a noun, and transcribed in the International Phonetic Alphabet as /ˈθɪknəs/. Corpus data places it at rank #10,464 in overall English word frequency, marking it as uncommon enough that many writers pause before typing it. Wiktionary records 6 distinct senses for this headword, so context determines which meaning a reader should apply.

Our generated misspelling index lists 13 likely wrong-spelling variants for thickness, with forms such as "htickness", "thcikness", and "thhickness". Each of these forms differs from the correct spelling by one small edit: a doubled letter, a dropped silent letter, or a substituted vowel. We don't track a confusable pairing for this entry, a sign it's visually distinctive enough not to be mixed up with another word.

Etymologically, the entry records: From Middle English thikkenesse, thiknesse, from Old English þicnes (“thickness, viscosity, density, hardness; obscurity, cloud, darkness; thicket; depth, a thick body, anything thick or heavy”), from Proto-West Germanic *þikkwīnassī (“thickness”), equivale… The correct English form is thickness, spelled T-H-I-C-K-N-E-S-S.

Definition

  1. 1
    The property of being thick (in dimension).
  2. 2
    A measure of how thick (in dimension) something is.
  3. 3
    A layer.
  4. 4
    The quality of being thick (in consistency).
  5. 5
    The property of being thick (slow to understand).
  6. 6
    The minimum number of planar subgraphs which a given graph can decompose into.

Etymology

From Middle English thikkenesse, thiknesse, from Old English þicnes (“thickness, viscosity, density, hardness; obscurity, cloud, darkness; thicket; depth, a thick body, anything thick or heavy”), from Proto-West Germanic *þikkwīnassī (“thickness”), equivalent to thick + -ness. Cognate with West Frisian tsjokkens (“thickness”), Old High German dickinessī, dikkinissi, diknissi (“thickness, density”). Eclipsed non-native Middle English crassitude (“thickness”) from Latin crassitūdō (“thickness”).

Synonyms

fatnessdepthlayerstratumdensityviscositydensenessslownessstupiditythickheadedness

Antonyms

fluidityliquidityrunninessthinnesswaterinessmental acuitymental agilityquick-wittednesssharpness

This word in other languages

grosor(Español)épaisseur(Français)Dicke(Deutsch)espessura(Português)

Common misspellings

Also misspelled as: htickness,thcikness,thhickness,thicckness,thickenss,thickkness,thicknes,thicknness,thicknses,thicnkess,thikcness,tihckness,tthickness

Misspelling Pattern Breakdown

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

htickness2thcikness2thhickness1thicckness1thickenss2thickkness1thicknes1thicknness1
Edit distance from "thickness"

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 "thickness"?
"thickness" is spelled T-H-I-C-K-N-E-S-S. The IPA pronunciation is /ˈθɪknəs/.
What does "thickness" mean?
As a noun, "thickness" means: The property of being thick (in dimension).
What are common misspellings of "thickness"?
Common misspellings include "htickness", "thcikness", "thhickness", "thicckness", "thickenss". The correct spelling is "thickness".
How do you pronounce "thickness"?
The IPA (International Phonetic Alphabet) transcription for "thickness" is /ˈθɪknəs/. 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 "thickness"?
From Middle English thikkenesse, thiknesse, from Old English þicnes (“thickness, viscosity, density, hardness; obscurity, cloud, darkness; thicket; depth, a thick body, anything thick or heavy”), from Proto-West Germanic *þikkwīnassī (“thickness”)... 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.

Using “thickness”

The practical upshot for anyone who landed here from a spell-check.

  • The one correct English spelling is T-H-I-C-K-N-E-S-S - every other letter order is a misspelling in standard orthography.
  • Say it as /ˈθɪknəs/ (IPA); tap the speaker on the pronunciation badge to hear it where audio exists.
  • Browse more English words and confusable pairs in the same reference. English words
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 FrequencyWords open word-frequency list