Of a period of time or (later) labour: characterized by adversity or hardship; gruelling; (in weakened sense) arduous, tiring.

Involving great hardships, painful exertion, unusual difficulty, etc.

Violent, harsh, severe. Of life, way of living, treatment, circumstances, etc.: harsh, grim; attended with or inflicting hardship. Of a wound…

Not easy. Of a situation, circumstance, period of time, etc.: characterized by or causing hardship or problems; adverse, troublesome; tricky, awkward.

Of immaterial things: Hard; harsh.

That involves great effort or hardship. Now frequently in weakened sense: tough, difficult.

colloquial. Of events and circumstances: difficult and unpleasant; unfortunate, unreasonable, unfair.

Involving hardships or discomfort.

Of circumstances, etc.: imposing hardship, distress, or injustice. colloquial (originally and chiefly U.S.).