arduous Synonyms

laborious strenuous hard exhausting burdensome grueling backbreaking operose trying straining wearisome demanding gruelling difficult fatiguing punishing painful toilsome onerous heavy strung thorny throbbing testing taxing stressful problematic rigorous rough rugged sanguineous serious severe sheer shingly sideling slaughterous sore ticklish tight tiring unenviable labor-intensive laboured bone dry brain surgery time-consuming nerve-wracking unbearable strugglesome