Definition of 'gruelling'

Adjective

1. characterized by toilsome effort to the point of exhaustion; especially physical effort; "worked their arduous way up the mining valley"; "a grueling campaign"; "hard labor"; "heavy work"; "heavy going"; "spent many laborious hours on the project"; "set a punishing pace"
      Synonyms: arduous backbreaking grueling hard heavy laborious operose punishing toilsome

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