WordNet sense 1 (unbearable physical pain):

torture

WordNet sense 2 (a feeling of intense annoyance caused by being tormented):

harassment

WordNet sense 3 (extreme mental distress):

anguish

WordNet sense 4 (intense feelings of suffering; acute mental or physical pain):

agony

WordNet sense 5 (a severe affliction):

curse

WordNet sense 6 (treat cruelly):

bedevil, crucify, dun, frustrate, rag

WordNet sense 7 (torment emotionally or mentally):

rack, excruciate

WordNet sense 8 (the act of harassing someone):

bedevilment, badgering, worrying