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severe; strict; rigid; unsparing; relentless
hard (to do); difficult; tricky
intense (e.g. cold); harsh (weather); inclement
今年の冬は酷しい寒さになりそうだ。
This winter looks like it will be severely cold.
酷しい訓練を乗り越えた。
I got through the rigorous training.
先生の評価は酷しかった。
The teacher's evaluation was strict.