arduous /ärˈdū-əs/

1. Steep, difficult to climb
2. Difficult to accomplish
3. Laborious

ardˈuously adverb

• ruggedly
• ruggedness
• ruggednesses
• ruggelach
• rugger
• rugger bugger
• rugger buggers
• ruggier
• ruggiest
• rugging
• ruggings
• rug gown
• rug gowns
• ruggy
• rug-headed
• rugose
• rugosely
• rugosities
• rugosity
• rugous
• rug rat
• rug rats
• rugs
• rugulose
• ruin