arduous 7 Associations

straining strenuous effortful (similar term)

arduousness 11 Associations

strenuousness effortfulness (generic term)

straining 9 Associations

arduous strenuous effortful (similar term)

strenuous 9 Associations

energetic (similar term)

strenuous 9 Associations

arduous straining effortful (similar term)

strenuousness 13 Associations

arduousness effortfulness (generic term)