punishing

(verb) impose a penalty on; inflict punishment on. Synonyms: punish, penalize, penalise. Examples: "The students were penalized for showing up late for class." "We had to punish the dog for soiling the floor again."

(adj) resulting in punishment. Example: "The king imposed a punishing tax."

(adj) characterized by effort to the point of exhaustion; especially physical effort. Synonyms: arduous, backbreaking, grueling, gruelling, hard, heavy, laborious, operose, toilsome. Examples: "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."