# arduous

> English word · Adjective · IPA /ˈɑː.djuː.əs/ · frequency rank #22,888

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

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

## Easily confused with
- **Aldous** (https://plainspell.com/en/vs/aldous-vs-arduous)

## Common misspellings (9)
`adruous`, `ardduous`, `ardouus`, `arduosu`, `arduouss`, `arduuos`, `arrduous`, `arudous`, `raduous`

## Source
Compiled from Wiktionary via kaikki.org (CC BY-SA). Data vintage: 2026-05-06.
Canonical page: https://plainspell.com/en/word/arduous