Longman Dictionary of Contemporary English - torment

~1 n 1 severe mental or physical suffering, often lasting a long time  (in torment)  (She lay awake all night in torment.) 2 someone or something that makes you suffer ~2 v 1 to make someone suffer a lot, especially so that they feel guilty or very unhappy  (Seth was tormented by feelings of guilt. | tormented by hunger) 2 to deliberately treat someone cruelly by annoying them or hurting them  (The older boys would torment him whenever they had the chance.) - tormentor n