Слово "weakness". Англо-русский словарь Мюллера

"But in weakness a man can be a great danger."

Others, even his nearest, knew only his strength; Edwards knew his weakness. He had seen Conway Jefferson tired, discouraged, weary of life, momentarily defeated by infirmity and loneliness.  

A weakness, beginning inwardly, extending to the limbs, seized me, and I fell: I lay on the ground some minutes, pressing my face to the wet turf.

“I suppose, Watson,” said he, “that you imagine that I have added opium-smoking to cocaine injections, and all the other little weaknesses on which you have favoured me with your medical views.”