arduous

/ˈɑː.djuː.əs/

//ˈɑː.djuː.əs// adj

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

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

The verdict

“arduous” has 9 generated spelling variants in the English index at frequency #22,888. The variants make it a useful spelling check.

#22,888
frequency rank, English
3,931
“A” headwords
9
tracked misspellings
1
confusable pair

According to Wiktionary data (CC BY-SA, analyzed September 3, 2026) - Needing or using up much energy; testing powers of endurance.

Corpus desk

Index EN-arduous · arduous · English

arduous · rank #22,888 · 9 variants · 1 confusable

  • FREQ-MID #22,888
  • LEN-LONG 7 letters
  • VOW-4 4 vowels
  • CONFUS-LOW 1 pairs
  • VAR-MID 9 variants
  • BOOK-MID 3,931
  • PHOTO-FINISH Asher

Nearest frequency peer: Asher (+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 “arduous”

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

corpus weight

What this shows “arduous” 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).

arduous vs Aldous
57% similar

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

Key facts for arduous
PropertyValue
Headwordarduous
LanguageEnglish
Part of speechAdjective
IPA/ˈɑː.djuː.əs/
Letters7
Frequency rank#22,888
Misspellings tracked9
Confusable pairs1
SourceWiktionary (kaikki.org)

Frequency seat of misspelling magnet “arduous”

Word frequency stretches from the small set of words we reach for constantly (left) out to the long tail barely used once in a while (right).arduouslands here:

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

The axis is logarithmic, with each marked tick roughly ten times rarer than the last. Same rarity band neighbours include “Asher” (#22,889), “Andromeda” (#22,886), “attaining” (#22,890). Among 3,931 “A” headwords, “arduous” is #22,888. Source: FrequencyWords open word-frequency list.

A misspelling magnet

The generator records 9 spelling variants around arduous (IPA /ˈɑː.djuː.əs/), anadjective. Corpus frequency is #22,888 among 3,931 “A” headwords. Wiktionary lists 3 senses, so context still picks the gloss.

Our generated misspelling index lists 9 likely wrong-spelling variants for arduous, with forms such as "adruous", "ardduous", and "ardouus". 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 1 confusable-pair relationship, "Aldous", a pairing that trips writers up because the two words share enough sound or shape to blur together.

Etymologically, the entry records: From Latin arduus (“lofty, high, steep, hard to reach, difficult, laborious”), akin to Irish ard (“high”). The correct English form is arduous, spelled A-R-D-U-O-U-S.

Definition

  1. 1
    Needing or using up much energy; testing powers of endurance.
  2. 2
    burning; ardent
  3. 3
    Difficult or exhausting to traverse.

Recorded use

Wiktionary examples

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

  1. The movement towards a peaceful settlement has been a long and arduous political struggle.
  2. Chelsea survived and can now turn their attentions to the Champions League final against Bayern Munich in Germany later this month as they face an increasingly arduous task to finish in the Premier League's top four.

Etymology

From Latin arduus (“lofty, high, steep, hard to reach, difficult, laborious”), akin to Irish ard (“high”).

Synonyms

burdensomedemandingexhaustingfatiguinglaboriousonerousstrenuousstrugglesomewearisomeuphill

This word in other languages

arduo(Español)ardu(Français)mühsam(Deutsch)árduo(Português)

Common misspellings

Also misspelled as:

  • adruous
  • ardduous
  • ardouus
  • arduosu
  • arduouss
  • arduuos
  • arrduous
  • arudous
  • raduous

Misspelling Pattern Breakdown

How far each generated variant is from the correct spelling of arduous - expressed in single-character edits (insert, delete, or swap one letter). Bigger bars stand out at a glance; a one-edit slip is the hardest to catch.

adruous2ardduous1ardouus2arduosu2arduouss1arduuos2arrduous1arudous2
Edit distance from "arduous"

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 "arduous"?
"arduous" is spelled A-R-D-U-O-U-S. The IPA pronunciation is /ˈɑː.djuː.əs/.
What does "arduous" mean?
As an adjective, "arduous" means: Needing or using up much energy; testing powers of endurance.
What words are commonly confused with "arduous"?
"arduous" is commonly confused with "Aldous". These words look or sound similar but have different meanings. PlainSpell provides detailed comparisons for each pair.
How do you pronounce "arduous"?
The IPA (International Phonetic Alphabet) transcription for "arduous" is /ˈɑː.djuː.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 "arduous"?
From Latin arduus (“lofty, high, steep, hard to reach, difficult, laborious”), akin to Irish ard (“high”). 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 "arduous", not the corpus desk frequency band.

Same letter count

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

Bavaria#22,899aborted#22,873zoology#22,869Buffett#22,912

Similar misspelling depth

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

Bangor9 variantswatery9 variantstracer9 variantsconcur9 variants

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

Source: FrequencyWords open word-frequency list