Synonyms for arduous

Similarity of adj arduous

3 senses of arduous

Sense 1:

arduous, backbreaking, grueling, gruelling, hard, heavy, laborious, operose, punishing, toilsome
effortful (vs. effortless)

Sense 2:

arduous, straining, strenuous
effortful (vs. effortless)

Sense 3:

arduous
difficult (vs. easy), hard