excruciating

adjective. extremely painful, mental or physical; agonizing

"I had excruciating pain in my knee and my toes went numb."
"an excruciating moment of embarrassment"
"For two years, Lindsey Vonn has been working hard and uncompromisingly for a comeback from excruciating knee injuries. Now she ties the women’s all-time record of World Cup wins."

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